Primitive operations on Sequential file in C language

Primitive operations on Sequential file in C language

 
 #include  
 #include  
 #include  
 typedef struct stud  
 {  
 int roll;  
 char name[20];  
 struct add  
 {  
 int hno;  
 char city[10];  
 }add;  
 char clas[4];  
 int mark;  
 }stud;  
 stud alloc(stud );  
 void insert(char [20]);  
 void create();  
 void display();  
 void searchnr(char [20]);  
 void searchcr(char [20]);  
 void modify();  
 void delet();  
 void main()  
 {  
 int ch,ch1;  
 char filename[20];  
 do  
 {  
 clrscr();  
 printf("\n\t\tFILE OPERATION\n\t\t1.CREATE\n\t\t2.INSERT\n\t\t3.DISPLAY\n\t\t4.SEARCH\n\t\t5.MODIFY\n\t\t6.DELETE\n\t\t7.EXIT");  
 printf("\n\t\tENTER UR CHOICE");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 1:  
 printf("\n\t\tCREATE");  
 create();  
 break;  
 case 2:  
 printf("\n\t\tINSERT");  
 printf("\nENTER FILENAME:");  
 flushall();  
 gets(filename);  
 insert(filename);  
 break;  
 case 3:  
 printf("\n\t\tDISPLAY");  
 display();  
 break;  
 case 4:  
 printf("\nENTER FILENAME:");  
 flushall();  
 gets(filename);  
 do  
 {  
 clrscr();  
 printf("\n\t\tSEARCH\n\t\t1.BY NAME N ROLL NO\n\t\t2.BY ROLL NO N CLASS\n\t\t3.EXIT");  
 printf("\n\t\tENTER UR CHOICE");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 printf("SEARCH BY NAME N ROLL NO");  
 searchnr(filename);  
 break;  
 case 2:  
 printf("SEARCH BY CLASS N ROLL NO");  
 searchcr(filename);  
 break;  
 case 3:  
 break;  
 }  
 }while(ch1!=3);  
 break;  
 case 5:  
 printf("\n\t\tMODIFY");  
 modify();  
 break;  
 case 6:  
 printf("\n\t\tDELETE");  
 delet();  
 break;  
 case 7:  
 break;  
 }  
 }while(ch!=7);  
 }  
 void create()  
 {  
 FILE *fp;  
 char filename[20];  
 printf("\nENTER THE FILE NAME:");  
 flushall();  
 gets(filename);  
 fp=fopen(filename,"r");  
 if(fp==NULL)  
 {  
 fclose(fp);  
 fopen(filename,"r");  
 }  
 else  
 {  
 printf("\nFILE IS ALREADY PRESENT,DO U WANT TO OVERWRITE PRESS 'y'");  
 if(getche()=='y')  
 {  
 fclose(fp);  
 fopen(filename,"w");  
 }  
 else  
 {  
 fclose(fp);  
 fopen(filename,"a");  
 }  
 }  
 fclose(fp);  
 do  
 {  
 insert(filename);  
 printf("DO U WANT TO CONTINUE:y/n");  
 }while(getche()=='y');  
 }  
 void insert(char filename[20])  
 {  
 FILE *fp;  
 char cl[10];  
 int i=0,r;  
 stud st,st1;  
 fp=fopen(filename,"r");  
 while(1)  
 {  
 printf("\nENTER ROLL NO:");  
 scanf("%d",&st.roll);  
 if(st.roll<0&&st.roll>60)  
 printf("\nINVALID ROLL NO");  
 else  
 break;  
 }  
 while(1)  
 {  
 printf("\nENTER CLASS:fe/se/te/be only");  
 scanf("%s",st.clas);  
 if(strcmp(st.clas,"fe")!=0&&strcmp(st.clas,"se")!=0&&strcmp(st.clas,"te")!=0&&strcmp(st.clas,"be")!=0)  
 printf("\nINVALID CLASS");  
 else  
 break;  
 }  
 if(fp==NULL)  
 {  
 printf("\nTHIS IS FIRST ENTRY IN THIS FILE");  
 }  
 else  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st1.roll,&st1.mark,&st1.add.hno,st1.add.city,st1.name,st1.clas);  
 if(st.roll==st1.roll&&(strcmp(st.clas,st1.clas))==0)  
 {  
 printf("\nALREADY PRESENT");  
 getch();  
 i++;  
 break;  
 }  
 }  
 fclose(fp);  
 fp=fopen(filename,"a");  
 if(i==0)  
 {  
 st=alloc(st);  
 fprintf(fp,"\n%d\n%d\n%d\n%s\n%s\n%s",st.roll,st.mark,st.add.hno,st.add.city,st.name,st.clas);  
 }  
 fclose(fp);  
 }  
 void display()  
 {  
 FILE *fp;  
 char filename[20];  
 int i=0;  
 stud st;  
 printf("\nENTER FILENAME:");  
 flushall();  
 gets(filename);  
 fp=fopen(filename,"r");  
 clrscr();  
 if(fp==NULL)  
 printf("\nFILE NOT FOUND");  
 else  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 printf("\nROLL NO:%d",st.roll);  
 printf("\nMARKS:%d",st.mark);  
 printf("\nHOUSE NO:%d",st.add.hno);  
 printf("\nCITY:%s",st.add.city);  
 printf("\nNAME:%s",st.name);  
 printf("\nCLASS:%s",st.clas);  
 i++;  
 getch();  
 if(i%2==0)  
 clrscr();  
 }  
 fclose(fp);  
 }  
 void searchnr(char filename[])  
 {  
 FILE *fp;  
 char nam[10];  
 int r,i=0;  
 stud st;  
 fp=fopen(filename,"r");  
 if(fp==NULL)  
 printf("\nFILE NOT FOUND");  
 else  
 {  
 printf("\nENTER ROLL NO:");  
 scanf("%d",&r);  
 printf("\nENTER NAME:");  
 scanf("%s",nam);  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 if(st.roll==r&&strcmp(st.name,nam)==0)  
 {  
 i=1;  
 printf("\nROLL NO:%d",st.roll);  
 printf("\nMARKS:%d",st.mark);  
 printf("\nHOUSE NO:%d",st.add.hno);  
 printf("\nCITY:%s",st.add.city);  
 printf("\nNAME:%s",st.name);  
 printf("\nCLASS:%s",st.clas);  
 getch();  
 }  
 }  
 }  
 if(i==0)  
 printf("\nNOT FOUND");  
 fclose(fp);  
 getch();  
 }  
 void searchcr(char filename[20])  
 {  
 FILE *fp;  
 char cl[10];  
 int r,i=0;  
 stud st;  
 fp=fopen(filename,"r");  
 if(fp==NULL)  
 printf("\nFILE NOT FOUND");  
 else  
 {  
 printf("\nENTER ROLL NO:");  
 scanf("%d",&r);  
 printf("\nENTER CLASS:");  
 scanf("%s",cl);  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 if(st.roll==r&&strcmp(st.clas,cl)==0)  
 {  
 i=1;  
 printf("\nROLL NO:%d",st.roll);  
 printf("\nMARKS:%d",st.mark);  
 printf("\nHOUSE NO:%d",st.add.hno);  
 printf("\nCITY:%s",st.add.city);  
 printf("\nNAME:%s",st.name);  
 printf("\nCLASS:%s",st.name);  
 getch();  
 break;  
 }  
 }  
 }  
 if(i==0)  
 printf("\nNOT FOUND");  
 fclose(fp);  
 getch();  
 }  
 void modify()  
 {  
 FILE *fp,*fp1;  
 char filename[20],filename1[20],cl[10];  
 int r,i=0,rol,ch;  
 stud st;  
 printf("\nENTER FILENAME:");  
 flushall();  
 gets(filename);  
 fp=fopen(filename,"r");  
 strcpy(filename1,"t");  
 strcat(filename1,filename);  
 fp1=fopen(filename1,"w");  
 if(fp==NULL)  
 printf("\nFILE NOT FOUND");  
 else  
 {  
 printf("\nENTER ROLL NO:");  
 scanf("%d",&rol);  
 printf("\nCLASS:");  
 scanf("%s",cl);  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 if(st.roll==rol&&strcmp(st.clas,cl)==0)  
 {  
 printf("\nOLD DAT IS:\nROLL NO:%d",st.roll);  
 printf("\nMARKS:%d",st.mark);  
 printf("\nHOUSE NO:%d",st.add.hno);  
 printf("\nCITY:%s",st.add.city);  
 printf("\nNAME:%s",st.name);  
 printf("\nCLASS:%s",st.clas);  
 getch();  
 do  
 {  
 clrscr();  
 printf("\nWHICH ENTRY U WANT TO MODIFY\n\t\t1.MARKS\n\t\t2.HOUSE NO\n\t\t3.CITY\n\t\t4.NAME\n\t\t5.EXIT");  
 printf("\nENTER UR CHOICE");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 1:  
 while(1)  
 {  
 printf("\nENTER NEW MARKS:");  
 scanf("%d",&st.mark);  
 if(st.mark<0&&st.mark>100)  
 printf("\nINVALID MARKS");  
 else  
 break;  
 getch();  
 }  
 break;  
 case 2:  
 while(1)  
 {  
 printf("\nENTER NEW HNO:");  
 scanf("%d",&st.add.hno);  
 if(st.add.hno<0&&st.add.hno>32000)  
 printf("\nINVALID h.NO");  
 else  
 break;  
 getch();  
 }  
 break;  
 case 3:  
 printf("\nENTER CITY:");  
 scanf("%s",st.add.city);  
 break;  
 case 4:  
 printf("\nENTER NAME:");  
 scanf("%s",st.name);  
 break;  
 case 5:  
 break;  
 }  
 }while(ch!=5);  
 i=1;  
 fprintf(fp1,"\n%d\n%d\n%d\n%s\n%s\n%s",st.roll,st.mark,st.add.hno,st.add.city,st.name,st.clas);  
 break;  
 }  
 else  
 fprintf(fp1,"\n%d\n%d\n%d\n%s\n%s\n%s",st.roll,st.mark,st.add.hno,st.add.city,st.name,st.clas);  
 }  
 }  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 fprintf(fp1,"\n%d\n%d\n%d\n%s\n%s\n%s",st.roll,st.mark,st.add.hno,st.add.city,st.name,st.clas);  
 }  
 fclose(fp);  
 fclose(fp1);  
 if(i==0)  
 {  
 printf("\nNOT FOUND");  
 remove(filename1);  
 }  
 else  
 {  
 remove(filename);  
 rename(filename1,filename);  
 }  
 getch();  
 }  
 void delet()  
 {  
 FILE *fp,*fp1;  
 char filename[20],cl[10],filename1[20];  
 int r,i=0;  
 stud st;  
 printf("\nENTER FILENAME:");  
 flushall();  
 gets(filename);  
 fp=fopen(filename,"r");  
 strcpy(filename1,"t");  
 strcat(filename1,filename);  
 fp1=fopen(filename1,"w");  
 if(fp==NULL)  
 printf("\nFILE NOT FOUND");  
 else  
 {  
 printf("\nENTER ROLL NO:");  
 scanf("%d",&r);  
 printf("\nENTER CLASS:");  
 scanf("%s",cl);  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 if(st.roll==r&&strcmp(st.clas,cl)==0)  
 {  
 i=1;  
 break;  
 }  
 else  
 fprintf(fp1,"\n%d\n%d\n%d\n%s\n%s\n%s",st.roll,st.mark,st.add.hno,st.add.city,st.name,st.clas);  
 }  
 }  
 while(!feof(fp))  
 {  
 fscanf(fp,"%d%d%d%s%s%s",&st.roll,&st.mark,&st.add.hno,st.add.city,st.name,st.clas);  
 fprintf(fp1,"\n%d\n%d\n%d\n%s\n%s\n%s",st.roll,st.mark,st.add.hno,st.add.city,st.name,st.clas);  
 }  
 fclose(fp);  
 fclose(fp1);  
 if(i==0)  
 {  
 printf("\nNOT FOUND");  
 remove("filename1");  
 }  
 else  
 {  
 remove(filename);  
 rename(filename1,filename);  
 printf("DATA IS DELETED");  
 }  
 getch();  
 }  
 stud alloc(stud st)  
 {  
 while(1)  
 {  
 printf("\nENTER MARKS:");  
 scanf("%d",&st.mark);  
 if(st.mark<0&&st.mark>100)  
 printf("\nINVALID ROLL NO");  
 else  
 break;  
 }  
 while(1)  
 {  
 printf("\nENTER HNO:");  
 scanf("%d",&st.add.hno);  
 if(st.add.hno<0&&st.add.hno>32000)  
 printf("\nINVALID ROLL NO");  
 else  
 break;  
 }  
 printf("\nENTER CITY:");  
 scanf("%s",st.add.city);  
 printf("\nENTER NAME:");  
 scanf("%s",st.name);  
 getch();  
 return st;  
 }

Dijkstra Algorithm in C Language

Represent a given graph using adjacency matrix and find the shortest path using Dijkstra’s algorithm. Use the map of the area around the college as the graph. Identify the prominent land marks as nodes and find minimum distance to various land marks from the college as the source.

Dijkstra Algorithm in C Language Code

#include  
 #include  
 #include  
 #include  
 #define MAX 20  
 #define INFINITE 32767  
 int *mat(int *,int,char[][20] );  
 int *freemat(int *);  
 void shortpath(int *,int,int,int,char[][20]);  
 int check(char[],char[][20]);  
 void main()  
 {  
 int ch,*visited,s,n,i,n1,*adj,d;  
 char str[20][20],str1[20];  
 adj=NULL;  
 do  
 {  
 clrscr();  
 printf("\n\t\tGRAPH\n\t\t1.ADJANCY MATRIX\n\t\t2.SHORTEST PATH\n\t\t\n\t\t3.EXIT");  
 printf("\n\t\tENTER UR CHOICE:");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 1:  
 if(adj!=NULL)  
 adj=freemat(adj);  
 printf("\n\t\tADJANCY MATRIX");  
 printf("ENTER NO OF NODES");  
 scanf("%d",&n1);  
 for(i=0;i<n1;i++) <br=""> {  
 printf("ENTER PLACE NO %d",i+1);  
 flushall();  
 gets(str[i]);  
 }  
 adj=mat(adj,n1,str);  
 break;  
 case 2:  
 if(adj==NULL)  
 printf("ENTER ADJENCY MATRIX FIRST");  
 else  
 {  
 while(1)  
 {  
 printf("\n\t\tENTER SOURCE");  
 flushall();  
 gets(str1);  
 s=check(str1,str);  
 if(s<n1) <br=""> break;  
 }  
 while(1)  
 {  
 printf("\n\t\tENTER DESTINATION");  
 flushall();  
 gets(str1);  
 d=check(str1,str);  
 if(d<n1) <br=""> break;  
 }  
 printf("SHORTEST PATH IS:");  
 shortpath(adj,s,d,n1,str);  
 }  
 getch();  
 break;  
 case 3:  
 break;  
 }  
 }while(ch!=3);  
 }  
 int * mat(int *adj,int n,char str[][20])  
 {  
 int s,d,w,i;  
 char so[20],de[20];  
 adj=(int *)calloc(n,n*2);  
 while(1)  
 {  
 printf("IS THERE ANY EDGES:y/n");  
 if(getche()=='n')  
 break;  
 printf("ENTER SOURCE");  
 flushall();  
 gets(so);  
 for(i=0;i<n;i++) <br=""> {  
 if(strcmp(so,str[i])==0)  
 break;  
 }  
 if(i==n)  
 printf("INVALID SOURCE");  
 else  
 {  
 s=i;  
 printf("ENTER DESTINATION");  
 flushall();  
 gets(de);  
 for(i=0;i<n;i++) <br=""> {  
 if(strcmp(de,str[i])==0)  
 break;  
 }  
 if(i==n)  
 printf("INVALID DESTINATION");  
 else  
 {  
 d=i;  
 if(*(adj+s*n+d)!=0)  
 printf("ALREADY PRESENT");  
 else  
 {  
 printf("ENTER DISTANCE B/W %s & %s",str[s],str[d]);  
 scanf("%d",&w);  
 *(adj+s*n+d)=w;  
 *(adj+d*n+s)=w;  
 }  
 }  
 }  
 }  
 return adj;  
 }  
 int *freemat(int *adj)  
 {  
 free(adj);  
 return NULL;  
 }  
 void shortpath(int *adj,int s,int d,int n,char str[][20])  
 {  
 int *visited,mincost,minver,i,j,k,m=0,*cost,*dest,path[20];  
 cost=(int *)malloc(2*n);  
 dest=(int *)malloc(2*n);  
 visited=(int *)calloc(1,2*n);  
 for(i=0;i<n;i++) <br=""> *(cost+i)=INFINITE;  
 j=s;  
 *(visited+s)=1;  
 while(*(visited+d)!=1)  
 {  
 mincost=INFINITE;  
 for(i=0;i<n;i++) <br=""> {  
 if(*(visited+i)!=1)  
 {  
 if(*(adj+s*n+i)!=0)  
 {  
 if(*(cost+i)>m+(*(adj+s*n+i)))  
 {  
 *(cost+i)=m+(*(adj+s*n+i));  
 *(dest+i)=s;  
 }  
 }  
 if(mincost>=*(cost+i))  
 {  
 mincost=*(cost+i);  
 minver=i;  
 }  
 }  
 }  
 m=mincost;  
 s=minver;  
 *(visited+s)=1;  
 }  
 printf("%d",*(cost+d));  
 getch();  
 i=d;  
 k=0;  
 path[k]=d;  
 k++;  
 while(i!=j)  
 {  
 path[k++]=*(dest+i);  
 i=*(dest+i);  
 }  
 k--;  
 printf("PATH IS");  
 while(k>0)  
 {  
 i=path[k];  
 printf("\n%s\t%s\t%d",str[i],str[path[k-1]],*(adj+i*n+path[k-1]));  
 k--;  
 }  
 getch();  
 free(visited);  
 free(cost);  
 free(dest);  
 }  
 int check(char str[],char str1[][20])  
 {  
 int s=0;  
 while(1)  
 {  
 flushall();  
 if(strcmp(str,str1[s])==0)  
 break;  
 s++;  
 }  
 return s;  
 }

Breadth First and Depth First Search C Language Graphs

 #include  
 #include  
 #include  
 #include  
 #define MAX 20  
 typedef struct graph  
 {  
 char vertex[MAX];  
 struct graph *link;  
 }graph;  
 void breadth(graph *,int ,int );  
 graph *list(int);  
 void depth(graph *,int ,int *,int);  
 graph *freelist(graph *,int);  
 void displaylist(graph *,int);  
 void main()  
 {  
 int ch,*visited,s,n,i,n1,j;  
 graph *g=NULL;  
 char str2[MAX],*str;  
 do  
 {  
 clrscr();  
 printf("\n\t\tGRAPH\n\t\t2.ADJANCY LIST\n\t\t3.DISPLAY OF ADJ MAT\n\t\t4.DISPLAY OF ADJ LIST\n\t\t5.DST OF ADJ LIST\n\t\t6.BST OF ADJ LIST\n\t\t9.EXIT");  
 printf("\n\t\tENTER UR CHOICE:");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 2:  
 if(g!=NULL)  
 g=freelist(g,n);  
 printf("ENTER NO OF NODES");  
 scanf("%d",&n);  
 printf("\n\t\tADJANCY LIST");  
 g=list(n);  
 break;  
 case 4:  
 printf("DISPLAY OF ADJ LIST");  
 break;  
 case 5:  
 if(g==NULL)  
 printf("ENTER ADJENCY LIST FIRST");  
 else  
 {  
 printf("\n\t\tDST OF ADJ LIST");  
 while(1)  
 {  
 printf("\n\t\tENTER SOURCE");  
 j=0;  
 flushall();  
 gets(str2);  
 while(1)  
 {  
 if(strcmp(str2,(g+j)->vertex)==0)  
 break;  
 j++;  
 }  
 if(j<n) <br=""> break;  
 }  
 visited=(int *)calloc(1,sizeof(int)*n);  
 depth(g,j,visited,n);  
 printf("ISOLATED VERTEX");  
 for(i=0;i<n;i++) <br=""> if(*(visited+i)==0)  
 printf("\n\t%s",(g+i)->vertex);  
 free(visited);  
 }  
 getch();  
 break;  
 case 6:  
 if(g==NULL)  
 printf("ENTER ADJENCY LIST FIRST");  
 else  
 {  
 printf("\n\t\tBST OF ADJ LIST");  
 while(1)  
 {  
 printf("\n\t\tENTER SOURCE");  
 j=0;  
 flushall();  
 gets(str2);  
 while(1)  
 {  
 if(strcmp(str2,(g+j)->vertex)==0)  
 break;  
 j++;  
 }  
 if(j<n) <br=""> break;  
 }  
 breadth(g,j,n);  
 }  
 getch();  
 break;  
 case 9:  
 break;  
 }  
 }while(ch!=9);  
 }  
 void depth(graph *f,int i,int *visited,int n)  
 {  
 graph *t;  
 int j=0;  
 printf("\t%s",(f+i)->vertex);  
 *(visited+i)=1;  
 t=(f+i)->link;  
 while(t!=NULL)  
 {  
 j=0;  
 while(1)  
 {  
 if(strcmp(t->vertex,(f+j)->vertex)==0)  
 break;  
 j++;  
 }  
 if(*(visited+j)!=1)  
 depth(f,j,visited,n);  
 t=t->link;  
 }  
 }  
 graph *freelist(graph *g,int n)  
 {  
 int i;  
 graph *q,*p,*k;  
 for(i=0;i<n;i++) <br=""> {  
 k=(g+i);  
 //PRINTF("\n%d",k->vertex);  
 q=k->link;  
 while(q!=NULL)  
 {  
 //printf("\t%d",q->link);  
 p=q; //(remove at d tym of display)  
 q=q->link;  
 free(p);//(remove at d tym of display)  
 }  
 }  
 p=g;  
 free(p);  
 return NULL;  
 }  
 void breadth(graph *f,int i,int n)  
 {  
 graph *queue[MAX],*q,*t;  
 int *visited,front=0,rear=0,j=0;  
 visited=(int *)calloc(1,sizeof(int)*n);  
 queue[rear]=(f+i);  
 *(visited+i)=1;  
 //q=f+i;  
 while(front!=-1)  
 {  
 q=queue[front];  
 j=0;  
 while(1)  
 {  
 if(strcmp(q->vertex,(f+j)->vertex)==0)  
 break;  
 j++;  
 }  
 q=f+j;  
 if(front==rear)  
 front=rear=-1;  
 else  
 front=(front+1)%MAX;  
 printf("\t%s",q->vertex);  
 t=q->link;  
 while(t!=NULL)  
 {  
 j=0;  
 while(1)  
 {  
 if(strcmp(t->vertex,(f+j)->vertex)==0)  
 break;  
 j++;  
 }  
 if(*(visited+j)==0)  
 {  
 if(front==-1)  
 front++;  
 rear=(rear+1)%MAX;  
 queue[rear]=t;  
 *(visited+j)=1;  
 }  
 t=t->link;  
 }  
 }  
 printf("ISOLATED VERTEX");  
 for(j=0;j<n;j++) <br=""> if(*(visited+j)==0)  
 printf("\n\t%s",(f+j)->vertex);  
 getch();  
 free(visited);  
 }  
 graph * list(int n)  
 {  
 graph *g=NULL,*p,*q,*nw;  
 char so[MAX],de[MAX];  
 int s,i,d;  
 g=(graph *)malloc(sizeof(graph)*n);  
 for(i=0;i<n;i++) <br=""> {  
 printf("ENTER DATA");  
 flushall();  
 gets(so);  
 strcpy((g+i)->vertex,so);  
 (g+i)->link=NULL;  
 }  
 while(1)  
 {  
 printf("\n\t\tIS THERE ANY EDGES:y/n");  
 if(getche()=='n')  
 break;  
 printf("ENTER SOURCE & DESTINATION");  
 flushall();  
 gets(so);  
 flushall();  
 gets(de);  
 for(s=0;s<n;s++) <br=""> if(strcmp((g+s)->vertex,so)==0)  
 break;  
 for(d=0;d<n;d++) <br=""> if(strcmp((g+d)->vertex,de)==0)  
 break;  
 if(s==n||strcmp(so,de)==0||d==n)  
 printf("INVALID");  
 else  
 {  
 p=(g+s);  
 q=p->link;  
 while(q!=NULL)  
 {  
 if(strcmp(q->vertex,de)==0)  
 {  
 printf("ALREADY PRESENT");  
 break;  
 }  
 p=q;  
 q=q->link;  
 }  
 if(q==NULL)  
 {  
 nw=(graph *)malloc(sizeof(graph));  
 nw->link=NULL;  
 strcpy(nw->vertex,de);  
 p->link=nw;  
 p=g+d;  
 while(p->link!=NULL)  
 p=p->link;  
 nw=(graph *)malloc(sizeof(graph));  
 nw->link=NULL;  
 strcpy(nw->vertex,so);  
 p->link=nw;  
 }  
 }  
 }  
 return g;  
 }

BFS AND DFS Algorithm using C Language

Represent a given graph using adjacency list and perform BFS AND DFS Algorithm. Use the map of the area around the college as the graph. Identify the prominent land marks as nodes and perform DFS and BFS on that.

BFS AND DFS Algorithm Code

 
 #include  
 #include  
 #include  
 #define MAX 30  
 typedef struct tree  
 {  
 char data[7];  
 struct tree *lc;  
 struct tree *rc;  
 }tree;  
 typedef struct stack1  
 {  
 int flag;  
 struct tree * addr;  
 struct stack1 *link;  
 }stack1;  
 tree *alloc();  
 tree * create();  
 tree * insert(tree *);  
 void recin(tree *);  
 void recpost(tree *);  
 void recpre(tree *);  
 void itin(tree *);  
 void itpost(tree *);  
 void itpre(tree *);  
 tree *delet(tree *,char[]);  
 tree *parent(tree *,tree *);  
 tree *succ(tree *,tree *);  
 tree *pre(tree *,tree *);  
 void search(tree *,char[]);  
 tree *search1(tree *,char[],int * );  
 void leveldis(tree *);  
 tree *mirror(tree *);  
 tree * freeall(tree *);  
 int depth(tree *,char[]);  
 int height(tree *);  
 void main()  
 {  
 int i=0,ch,ch1,data;  
 char d[7];  
 tree *f=NULL,*f1=NULL;  
 do  
 {  
 clrscr();  
 printf("\n\t\tBST TREE OPERATION\n\t\t1.CREATE\n\t\t2.INSERT\n\t\t3.DELETE");  
 printf("\n\t\t4.SEARCH\n\t\t5.RECURSIVE TRAVERSE\n\t\t6.ITERATIVE TRAVERSE");  
 printf("\n\t\t7.DEPTH OF TREE\n\t\t8.MIRROR IMAGE\n\t\t9.LEVEL WISE DISPLAY MIRROR IMAGE\n\t\t10.HEIGHT OF TREE\n\t\t11.EXIT\n\t\tENTER UR CHOICE");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 1:  
 if(f!=NULL)  
 f=freeall(f);  
 printf("\n\t\tCREATE");  
 f=create();  
 break;  
 case 2:  
 if(f==NULL)  
 printf("CREATE FIRST");  
 else  
 {  
 printf("\n\t\tINSERT");  
 f=insert(f);  
 }  
 break;  
 case 3:  
 if(f==NULL)  
 printf("CREATE FIRST");  
 else  
 {  
 printf("\n\t\tDELETE\n\t\tENTER DATA");  
 flushall();  
 gets(d);  
 f=delet(f,d);  
 }  
 break;  
 case 4:  
 if(f==NULL)  
 printf("CREATE FIRST");  
 else  
 {  
 printf("\n\t\tSEARCH\n\t\tENTER DATA");  
 flushall();  
 gets(d);  
 search(f,d);  
 }  
 break;  
 case 5:  
 if(f==NULL)  
 printf("\n\t\tENTER INPUT FIRST");  
 else  
 do  
 {  
 clrscr();  
 printf("\n\t\tRECURSIVE TRAVERSE MENU\n\t\t1.INORDER\n\t\t2.POSTORDER\n\t\t3.PREORDER\n\t\t4.EXIT");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 printf("\n\t\tINORDER");  
 recin(f);  
 break;  
 case 2:  
 printf("\n\t\tPOSTORDER");  
 recpost(f);  
 break;  
 case 3:  
 printf("\n\t\tPREORDER");  
 recpre(f);  
 break;  
 case 4:  
 break;  
 default:  
 printf("\n\t\tINVALID CHOICE");  
 }  
 getch();  
 }while(ch1!=4);  
 getch();  
 break;  
 case 6:  
 if(f==NULL)  
 printf("\n\t\tENTER INPUT FIRST");  
 else  
 do  
 {  
 clrscr();  
 printf("\n\t\tITERATIVE TRAVERSE MENU\n\t\t1.INORDER\n\t\t2.POSTORDER\n\t\t3.PREORDER\n\t\t4.EXIT");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 printf("\n\t\tINORDER");  
 itin(f);  
 break;  
 case 2:  
 printf("\n\t\tPOSTORDER");  
 itpost(f);  
 break;  
 case 3:  
 printf("\n\t\tPREORDER");  
 itpre(f);  
 break;  
 case 4:  
 break;  
 default:  
 printf("\n\t\tINVALID CHOICE");  
 }  
 }while(ch1!=4);  
 getch();  
 break;  
 case 7:  
 if(f==NULL)  
 printf("CREATE FIRST");  
 else  
 {  
 printf("\n\t\tDEPTH OF TREE\n\t\tENTER DATA");  
 flushall();  
 gets(d);  
 i=depth(f,d);  
 if(i!=-1)  
 printf("DEPTH OF GIVEN NODE IS %d",i);  
 getch();  
 }  
 break;  
 case 8:  
 if(f==NULL)  
 printf("CREATE FIRST");  
 else  
 {  
 if(f1!=NULL)  
 f1=freeall(f1);  
 printf("\n\t\tMIRROR OF TREE");  
 f1=mirror(f);  
 recin(f1);  
 getch();  
 }  
 break;  
 case 9:  
 if(f1==NULL)  
  printf("CREATE MIRROR IMAGE FIRST");  
 else  
 {  
 printf("\n\t\tLEVEL WISE MIRROR OF TREE");  
 leveldis(f1);  
 }  
 break;  
 case 10:  
 if(f==NULL)  
  printf("CREATE FIRST");  
 else  
 {  
 printf("\n\t\theight OF TREE:");  
 i=height(f);  
 printf("%d",i);  
 }  
 break;  
 case 11:  
 break;  
 }  
 getch();  
 }while(ch!=11);  
 }  
 tree * create()  
 {  
 tree *root=NULL;  
 do  
 {  
 root=insert(root);  
 printf("DO U WANT TO ENTER MORE");  
 }while(getche()=='y'||getche()=='Y');  
 return root;  
 }  
 tree *alloc()  
 {  
 tree *nw;  
 nw=(tree *)malloc(sizeof(tree));  
 nw->lc=nw->rc=NULL;  
 printf("ENTER DATA");  
 flushall();  
 gets(nw->data);  
 return nw;  
 }  
 tree * insert(tree *root)  
 {  
 tree *nw,*t;  
 nw=alloc();  
 if(root==NULL)  
 return nw;  
 t=root;  
 while(1)  
 {  
 if(strcmp(nw->data,t->data)<0)  
 {  
 if(t->lc==NULL)  
 {  
 t->lc=nw;  
 return root;  
 }  
 t=t->lc;  
 }  
 else if(strcmp(nw->data,t->data)>0)  
 {  
 if(t->rc==NULL)  
 {  
 t->rc=nw;  
 return root;  
 }  
 t=t->rc;  
 }  
 else  
 {  
 printf("ALREADY PRESNT");  
 free(nw);  
 break;  
 }  
 }  
 return root;  
 }  
 void recin(tree *root)  
 {  
 if(root!=NULL)  
 {  
 recin(root->lc);  
 puts(root->data);  
 recin(root->rc);  
 }  
 }  
 void recpost(tree *root)  
 {  
 if(root!=NULL)  
 {  
 recpost(root->lc);  
 recpost(root->rc);  
 puts(root->data);  
 }  
 }  
 void recpre(tree *root)  
 {  
 if(root!=NULL)  
 {  
 puts(root->data);  
 recpre(root->lc);  
 recpre(root->rc);  
 }  
 }  
 void itin(tree *root)  
 {  
 tree *t;  
 tree *st[30];  
 int top=-1;  
 t=root;  
 while(t!=NULL||top!=-1)  
 {  
 if(t!=NULL)  
 {  
 st[++top]=t;  
 t=t->lc;  
 }  
 else  
 {  
 t=st[top--];  
 puts(t->data);  
 t=t->rc;  
 }  
 }  
 getch();  
 }  
 void itpre(tree *root)  
 {  
 tree *t;  
 tree *st[30];  
 int top=-1;  
 t=root;  
 while(t!=NULL||top!=-1)  
 {  
 if(t!=NULL)  
 {  
 puts(t->data);  
 st[++top]=t;  
 t=t->lc;  
 }  
 else  
 {  
 t=st[top--];  
 t=t->rc;  
 }  
 }  
 getch();  
 }  
 void itpost(tree *root)  
 {  
 tree *t;  
 stack1 *top,*nw;  
 top=NULL;  
 t=root;  
 while(t!=NULL||top!=NULL)  
 {  
 if(t!=NULL)  
 {  
 nw=(stack1 *)malloc(sizeof(stack1));  
 nw->addr=t;  
 nw->link=top;  
 nw->flag=0;  
 top=nw;  
 t=t->lc;  
 }  
 else  
 {  
 t=top->addr;  
 if(top->flag==0)  
 {  
 top->flag=1;  
 t=t->rc;  
 }  
 else  
 {  
 puts(t->data);  
 nw=top;  
 top=top->link;  
 free(nw);  
 t=NULL;  
 }  
 }  
 }  
 getch();  
 }  
 tree * freeall(tree *t)  
 {  
 tree * q;  
 q=t;  
 if(t!=NULL)  
 {  
 t=freeall(t->lc);  
 t=freeall(q->rc);  
 free(q);  
 }  
 return NULL;  
 }  
 tree *delet(tree *root,char val[])  
 {  
 tree *d,*s,*c,*p,*node;  
 int i=0;  
 p=root;  
 node=search1(root,val,&i);  
 if(i!=0)  
 {  
 if(node->rc!=NULL&&node->lc!=NULL)  
 {  
 printf("WANT TO DELETE BY SUCCESSOR PRESS 'y' ,PRESS ANY KEY FOR PREDECCESOR");  
 if(getche()=='y')  
 s=succ(root,node);  
 else  
 s=pre(root,node);  
 }  
 else  
 s=node;  
 if(s->lc!=NULL)  
 c=s->lc;  
 else  
 c=s->rc;  
 p=parent(root,s);  
 if(p==NULL)  
 {  
 root=c;  
 free(root);  
 return c;  
 }  
 if(p->lc==s)  
 p->lc=c;  
 else  
 p->rc=c;  
 if(s!=node)  
 strcpy(node->data,s->data);  
 free(s);  
 printf("DELETED");  
 }  
 else  
 printf("NOT FOUND");  
 getch();  
 return root;  
 }  
 tree *parent(tree *root,tree *node)  
 {  
 tree *p;  
 p=root;  
 if(strcmp(p->data,node->data)==0)  
 p=NULL;  
 else  
 while(p!=NULL)  
 {  
 if(strcmp(p->data,node->data)<0)  
 {  
 if(p->rc==node)  
 return p;  
 p=p->rc;  
 }  
 else  
 {  
 if(p->lc==node)  
 break;  
 p=p->lc;  
 }  
 }  
 return p;  
 }  
 tree *succ(tree *root,tree *node)  
 {  
 tree *t,*p;  
 if(node->rc!=NULL)  
 {  
 t=node->rc;  
 while(t->lc!=NULL)  
 t=t->lc;  
 return t;  
 }  
 t=node;  
 p=parent(root,node);  
 while(p->lc!=t&&t!=NULL)  
 {  
 t=p;  
 p=succ(root,t);  
 }  
 return p;  
 }  
 tree *pre(tree *root,tree *node)  
 {  
 tree *t,*p;  
 if(node->lc!=NULL)  
 {  
 t=node->lc;  
 while(t->rc!=NULL)  
 t=t->rc;  
 return t;  
 }  
 t=node;  
 p=parent(root,node);  
 while(p->rc!=t&&t!=NULL)  
 {  
 t=p;  
 p=succ(root,t);  
 }  
 return p;  
 }  
 void search(tree *root,char val[])  
 {  
 tree *t,*q;  
 t=root;  
 if(strcmp(val,root->data)!=0)  
 {  
 if(strcmp(val,t->data)>0)  
 q=t->rc;  
 else if(strcmp(val,t->data)<0)  
 q=t->lc;  
 while(q!=NULL)  
 {  
 if(strcmp(val,q->data)>0)  
 q=q->rc;  
 else if(strcmp(val,q->data)<0)  
 q=q->lc;  
 else  
 break;  
 if(strcmp(q->data,t->data)>0)  
 t=t->rc;  
 else if(strcmp(q->data,t->data)<0)  
 t=t->lc;  
 }  
 }  
 else  
 q=root;  
 if(q==NULL)  
 printf("\nNOT FOUND");  
 else  
 {  
 if(q==root)  
 printf("\nIT IS ROOT NODE");  
 else  
 {  
 printf("\nITS PARENT IS:");  
 puts(t->data);  
 }  
 if(q->lc==NULL&&q->rc==NULL)  
 printf("\nIT IS A LEAF NODE");  
 else  
 {  
 if(q->lc!=NULL)  
 {  
 printf("\nITS LEFT CHILD IS:");  
 puts(q->lc->data);  
 }  
 else  
 printf("\nLEFT CHILD IS NOT PRESENT");  
 if(q->rc!=NULL)  
 {  
 printf("\nITS RIGHT CHILD IS:");  
 puts(q->rc->data);  
 }  
 else  
 printf("\nRIGHT CHILD IS NOT PRESENT");  
 }  
 }  
 getch();  
 }  
 tree *mirror(tree *root)  
 {  
 tree *t,*q,*f=NULL,*nw;  
 tree *st[20][2];  
 int top=-1;  
 t=root;  
 while(t!=NULL||top!=-1)  
 {  
 nw=(tree *)malloc(sizeof(tree));  
 nw->lc=NULL;  
 nw->rc=NULL;  
 if(t==NULL)  
 {  
 t=st[top][0];  
 q=st[top--][1];  
 q->lc=nw;  
 q=q->lc;  
 }  
 else if(t!=root)  
 {  
 q->rc=nw;  
 q=q->rc;  
 }  
 if(f==NULL)  
 {  
 f=nw;  
 q=f;  
 }  
 strcpy(q->data,t->data);  
 if(t->rc!=NULL)  
 {  
 st[++top][0]=t->rc;  
 st[top][1]=q;  
 }  
 t=t->lc;  
 }  
 return f;  
 }  
 void leveldis(tree *f)  
 {  
 tree *queue[MAX],*t;  
 int front=-1,rear=-1,i=-1,pl=0,cl=1;  
 t=f;  
 if(front==-1)  
 front++;  
 rear=(rear+1)%MAX;  
 queue[rear]=t;  
 while(cl!=0||pl!=0)  
 {  
 if(pl==0)  
 {  
 i++;  
 printf("\nELEMENT IN %d LEVEL:",i);  
 pl=cl;  
 cl=0;  
 }  
 t=queue[front];  
 if(front==rear)  
 front=rear=-1;  
 else  
 front=(front+1)%MAX;  
 puts(t->data);  
 if(t->lc!=NULL)  
 {  
 if(front==-1)  
 front++;  
 rear=(rear+1)%MAX;  
 queue[rear]=t->lc;  
 cl++;  
 }  
 if(t->rc!=NULL)  
 {  
 if(front==-1)  
 front++;  
 rear=(rear+1)%MAX;  
 queue[rear]=t->rc;  
 cl++;  
 }  
 pl--;  
 }  
 getch();  
 }  
 int depth(tree *root,char val[])  
 {  
 tree *t,*node;  
 int i=0;  
 t=root;  
 while(t!=NULL)  
 {  
 if(strcmp(val,t->data)==0)  
 return i;  
 else if(strcmp(val,t->data)<0)  
 {  
 i++;  
 t=t->lc;  
 }  
 else  
 {  
 i++;  
 t=t->rc;  
 }  
 }  
 printf("NOT FOUND");  
 getch();  
 return -1;  
 }  
 tree* search1(tree *root,char val[],int *i)  
 {  
 tree *t;  
 t=root;  
 while(t!=NULL)  
 {  
 if(strcmp(val,t->data)>0)  
 t=t->rc;  
 else if(strcmp(val,t->data)<0)  
 t=t->lc;  
 else  
 {  
 *i=1;  
 break;  
 }  
 }  
 return t;  
 }  
 int height(tree *t)  
 {  
 int hl,hr;  
 if(t==NULL)  
 return 0;  
 if(t->lc==NULL&&t->rc==NULL)  
 return 0;  
 hl=height(t->lc);  
 hr=height(t->rc);  
 if(hl>hr)  
 return(hl+1);  
 return(hr+1);  
 }

Expression Tree in C

Write a program to implement Expression Tree using C Language with the following features :

• Recursive Traverse
• Iterative Traverse

 
 #include  
 #include  
 #include  
 typedef struct tree  
 {  
 char data;  
 struct tree *lc;  
 struct tree *rc;  
 }tree;  
 typedef struct stack1  
 {  
 int flag;  
 struct tree * addr;  
 struct stack1 *link;  
 }stack1;  
 tree * freeall(tree *);  
 void prefix(char []);  
 void postfix(char []);  
 void display(char []);  
 tree *ptprefix(char [],int *);  
 tree *ptpostfix(char [],int *);  
 tree *alloc(char);  
 void recin(tree *);  
 void recpost(tree *);  
 void recpre(tree *);  
 void itin(tree *);  
 void itpre(tree *);  
 void itpost(tree *);  
 void main()  
 {  
 int ch,ch1,i;  
 char str[50];  
 tree *f=NULL;  
 clrscr();  
 do  
 {  
 clrscr();  
 printf("\n\t\t1.INPUT\n\t\t2.RECURSIVE TRAVERSE\n\t\t3.ITERATIVE TRAVERSE\n\t\t4.EXIT");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 1:  
 printf("\n\t\tINPUT MENU\n\t\t1.PREFIX EXPRESSION\n\t\t2.POSTFIX EXPRESSION\n\t\t3.EXIT");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 if(f!=NULL)  
 f=freeall(f);  
 printf("\n\t\tPREFIX EXPRESSION");  
 prefix(str);  
 i=0;  
 f=ptprefix(str,&i);  
 break;  
 case 2:  
 if(f!=NULL)  
 f=freeall(f);  
 printf("\n\t\tPOSTFIX EXPRESSION");  
 postfix(str);  
 i=strlen(str)-1;  
 f=ptpostfix(str,&i);  
 break;  
 case 3:  
 break;  
 default:  
 printf("\n\t\tINVALID CHOICE");  
 }  
 break;  
 case 2:  
 if(f==NULL)  
 printf("\n\t\tENTER INPUT FIRST");  
 else  
 do  
 {  
 clrscr();  
 printf("\n\t\tRECURSIVE TRAVERSE MENU\n\t\t1.INORDER\n\t\t2.POSTORDER\n\t\t3.PREORDER\n\t\t4.EXIT");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 printf("\n\t\tINORDER");  
 recin(f);  
 break;  
 case 2:  
 printf("\n\t\tPOSTORDER");  
 recpost(f);  
 break;  
 case 3:  
 printf("\n\t\tPREORDER");  
 recpre(f);  
 break;  
 case 4:  
 break;  
 default:  
 printf("\n\t\tINVALID CHOICE");  
 }  
 getch();  
 }while(ch1!=4);  
 getch();  
 break;  
 case 3:  
 if(f==NULL)  
 printf("\n\t\tENTER INPUT FIRST");  
 else  
 do  
 {  
 clrscr();  
 printf("\n\t\tITERATIVE TRAVERSE MENU\n\t\t1.INORDER\n\t\t2.POSTORDER\n\t\t3.PREORDER\n\t\t4.EXIT");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 printf("\n\t\tINORDER");  
 itin(f);  
 break;  
 case 2:  
 printf("\n\t\tPOSTORDER");  
 itpost(f);  
 break;  
 case 3:  
 printf("\n\t\tPREORDER");  
 itpre(f);  
 break;  
 case 4:  
 break;  
 default:  
 printf("\n\t\tINVALID CHOICE");  
 }  
 }while(ch1!=4);  
 getch();  
 break;  
 case 4:  
 break;  
 default:  
 printf("\n\t\tINVALID CHOICE");  
 }  
 }while(ch!=4);  
 }  
 void prefix(char str[])  
 {  
 int i=0,rank=0;  
 while(1)  
 {  
 str[i++]=getche();  
 if(str[i-1]=='\r'&&i>2&&rank==1)  
 break;  
 else if(rank!=1&&(str[i-1]=='+'||str[i-1]=='-'||str[i-1]=='*'|| str[i-1]=='^'||str[i-1]=='/'))  
 rank=rank-1;  
 else if(((str[i-1]>=48&&str[i-1]<=57)||(str[i-1]>=65&&str[i-1]<=90)||(str[i-1]>=97&&str[i-1]<=122)))  
 rank=rank+1;  
 else  
 {  
 printf("\nINVALID ENTRY");  
 i=0;  
 rank=0;  
 }  
 if(rank>1)  
 {  
 printf("\nINVALID ENTRY");  
 i=0;  
 rank=0;  
 }  
 }  
 str[i-1]=NULL;  
 }  
 void postfix(char str[])  
 {  
 int i=0,rank=0;  
 while(1)  
 {  
 str[i++]=getche();  
 if(str[i-1]=='\r'&&i>2&&rank==1)  
 break;  
 if(i>1&&(str[i-1]=='+'||str[i-1]=='-'||str[i-1]=='*'|| str[i-1]=='^'||str[i-1]=='/'))  
 rank=rank-1;  
 else if((str[i-1]>=48&&str[i-1]<=57)||(str[i-1]>=65&&str[i-1]<=90)||(str[i-1]>=97&&str[i-1]<=122))  
 rank=rank+1;  
 else  
 {  
 printf("\nINVALID ENTRY");  
 i=0;  
 rank=0;  
 }  
 if(rank<1)  
 {  
 printf("\nINVALID ENTRY");  
 i=0;  
 rank=0;  
 }  
 }  
 str[i-1]=NULL;  
 }  
 tree *ptprefix(char str[],int *i)  
 {  
 tree *nw;  
 nw=alloc(str[(*i)]);  
 if(str[(*i)]=='+'||str[(*i)]=='-'||str[(*i)]=='*'|| str[(*i)]=='^'||str[(*i)]=='/')  
 {  
 ++*i;  
 nw->lc=ptprefix(str,i);  
 ++*i;  
 nw->rc=ptprefix(str,i);  
 }  
 return nw;  
 }  
 tree * alloc(char c)  
 {  
 tree *nw;  
 nw=(tree *)malloc(sizeof(tree));  
 nw->data=c;  
 nw->lc=NULL;  
 nw->rc=NULL;  
 return nw;  
 }  
 tree *ptpostfix(char str[],int *i)  
 {  
 tree *nw;  
 char c;  
 nw=alloc(str[(*i)]);  
 if(str[(*i)]=='+'||str[(*i)]=='-'||str[(*i)]=='*'|| str[(*i)]=='^'||str[(*i)]=='/')  
 {  
 --*i;  
 nw->rc=ptpostfix(str,i);  
 --*i;  
 nw->lc=ptpostfix(str,i);  
 }  
 return nw;  
 }  
 void recin(tree *root)  
 {  
 if(root!=NULL)  
 {  
 if(root->lc!=NULL)  
 printf("(");  
 recin(root->lc);  
 printf("%c",root->data);  
 recin(root->rc);  
 if(root->rc!=NULL)  
 printf(")");  
 }  
 }  
 void recpost(tree *root)  
 {  
 if(root!=NULL)  
 {  
 recpost(root->lc);  
 recpost(root->rc);  
 printf("%c",root->data);  
 }  
 }  
 void recpre(tree *root)  
 {  
 if(root!=NULL)  
 {  
 printf("%c",root->data);  
 recpre(root->lc);  
 recpre(root->rc);  
 }  
 }  
 void itpre(tree *root)  
 {  
 tree *t;  
 tree *st[30];  
 int top=-1;  
 t=root;  
 while(t!=NULL||top!=-1)  
 {  
 if(t!=NULL)  
 {  
 printf("%c",t->data);  
 st[++top]=t;  
 t=t->lc;  
 }  
 else  
 {  
 t=st[top--];  
 t=t->rc;  
 }  
 }  
 getch();  
 }  
 void itpost(tree *root)  
 {  
 tree *t;  
 stack1 *top,*nw;  
 top=NULL;  
 t=root;  
 while(t!=NULL||top!=NULL)  
 {  
 if(t!=NULL)  
 {  
 nw=(stack1 *)malloc(sizeof(stack1));  
 nw->addr=t;  
 nw->link=top;  
 nw->flag=0;  
 top=nw;  
 t=t->lc;  
 }  
 else  
 {  
 t=top->addr;  
 if(top->flag==0)  
 {  
 top->flag=1;  
 t=t->rc;  
 }  
 else  
 {  
 printf("%c",t->data);  
 nw=top;  
 top=top->link;  
 free(nw);  
 t=NULL;  
 }  
 }  
 }  
 getch();  
 }  
 tree * freeall(tree *t)  
 {  
 tree * q;  
 q=t;  
 if(t!=NULL)  
 {  
 t=freeall(t->lc);  
 t=freeall(q->rc);  
 free(q);  
 }  
 return NULL;  
 }  
 void itin(tree *root)  
 {  
 tree *t;  
 stack1 *top,*nw;  
 top=NULL;  
 t=root;  
 while(t!=NULL||top!=NULL)  
 {  
 if(t!=NULL)  
 {  
 if(t->lc!=NULL)  
 printf("(");  
 nw=(stack1 *)malloc(sizeof(stack1));  
 nw->addr=t;  
 nw->link=top;  
 nw->flag=0;  
 top=nw;  
 t=t->lc;  
 }  
 else  
 {  
 t=top->addr;  
 if(top->flag==0)  
 {  
 top->flag=1;  
 printf("%c",t->data);  
 t=t->rc;  
 }  
 else  
 {  
 nw=top;  
 top=top->link;  
 t=nw->addr;  
 free(nw);  
 if(t->rc!=NULL)  
 printf(")");  
 t=NULL;  
 }  
 }  
 }  
 getch();  
 }

Queue Operations using C Language

Write a program to Queue Operations using C Language to implement the following functions :

• Create Queue
• Delete Queue
• Display Queue
• Delete Queue

Queue Operations using C Language Code

#include  
 #include  
 #include  
 typedef struct queue  
 {  
 char name[20];  
 char diesease[50];  
 struct add  
 {  
 int hno;  
 int sno;  
 char city[20];  
 }add;  
 struct queue * link;  
 }queue;  
 typedef struct prior  
 {  
 queue * front;  
 queue * rear;  
 int priority;  
 struct prior * next;  
 }prior;  
 prior *create();  
 prior *delet(prior *);  
 void display(queue *,int *);  
 void alloc(queue *);  
 prior *freeall(prior *);  
 void main()  
 {  
 int ch,ch1,temp;  
 prior *t,*f=NULL;  
 do  
 {  
 clrscr();  
 printf("\n\t1.CREATE\n\t2.DELETE\n\t3.DISPLAY\n\t4.EXIT\n\tENTER UR CHOICE:");  
 scanf("%d",&ch);  
 switch(ch)  
 {  
 case 1: if(f!=NULL)  
 f=freeall(f);  
 printf("\nCREATE");  
 f=create();  
 break;  
 case 2:  
 if(f==NULL)  
 printf("FIRST CREATE !!!!!");  
 else  
 {  
 printf("\nDELETE");  
 f=delet(f);  
 }  
 getch();  
 break;  
 case 3:  
 if(f==NULL)  
 printf("FIRST CREATE !!!!!");  
 else  
 {  
 do  
 {  
 clrscr();  
 printf("\n\tDISPLAY\n\t1.BY CATEGORY\n\t2.ALL\n\t3.EXIT\n\tENTER UR CHOICE");  
 scanf("%d",&ch1);  
 switch(ch1)  
 {  
 case 1:  
 printf("\nENTER THE CATEGORY:\n1.SERIOUS\n2.NON-SERIOUS\n3.GENERAL");  
 scanf("%d",&ch);  
 temp=1;  
 t=f;  
 clrscr();  
 while(t!=NULL)  
 {  
 if(t->priority==ch)  
 break;  
 t=t->next;  
 }  
 if(t!=NULL)  
 display(t->front,&temp);  
 else  
 printf("NOT FOUND");  
 getch();  
 break;  
 case 2:  
 t=f;  
 temp=1;  
 clrscr();  
 while(t!=NULL)  
 {  
 display(t->front,&temp);  
 t=t->next;  
 }  
 getch();  
 break;  
 case 3:  
 break;  
 default:printf("\nINVALID CHOICE");  
 }  
 }while(ch1!=3);  
 }  
 getch();  
 break;  
 case 4:  
 break;  
 default:printf("\nINVALID CHOICE");  
 }  
 }while(ch!=4);  
 getch();  
 }  
 prior * create()  
 {  
 int p;  
 prior *f=NULL,*nw1,*t;  
 queue *nw;  
 do  
 {  
 nw=(queue *)malloc(sizeof(queue));  
 nw->link=NULL;  
 alloc(nw);  
 printf("\nGIVE THE PRIORITY TO THIS PATIENT:");  
 while(1)  
 {  
 scanf("%d",&p);  
 if(p>0&&p<4)  
 break;  
 else  
 printf("INVALID PRIORITY");  
 }  
 if(f==NULL)  
 {  
 nw1=(prior *)malloc(sizeof(prior));  
 nw1->next=NULL;  
 nw1->priority=p;  
 nw1->front=nw;  
 nw1->rear=nw;  
 f=nw1;  
 }  
 else  
 {  
 if(f->priority>p)  
 {  
 nw1=(prior *)malloc(sizeof(prior));  
 nw1->next=NULL;  
 nw1->priority=p;  
 nw1->front=nw;  
 nw1->rear=nw;  
 nw1->next=f;  
 f=nw1;  
 }  
 t=f;  
 while(p>=t->next->priority&&t->next!=NULL)  
 t=t->next;  
 if(p==t->priority)  
 {  
 t->rear->link=nw;  
 t->rear=nw;  
 }  
 else  
 {  
 nw1=(prior *)malloc(sizeof(prior));  
 nw1->next=NULL;  
 nw1->priority=p;  
 nw1->front=nw;  
 nw1->rear=nw;  
 nw1->next=t->next;  
 t->next=nw1;  
 }  
 }  
 printf("DO U WANT TO ENTER MORE:");  
 }while(getche()=='y'||getche()=='Y');  
 return f;  
 }  
 void alloc(queue *nw)  
 {  
 printf("\nENTER NAME:");  
 flushall();  
 gets(nw->name);  
 printf("\nENTER DIESEASE:");  
 flushall();  
 gets(nw->diesease);  
 printf("\nENTER H.NO:");  
 scanf("%d",&(nw->add.hno));  
 printf("\nENTER S.NO:");  
 scanf("%d",&(nw->add.sno));  
 printf("\nENTER CITY:");  
 flushall();  
 gets(nw->add.city);  
 }  
 void display(queue *t,int *temp)  
 {  
 while(t!=NULL)  
 {  
 printf("\n\nNAME:");  
 printf("%s",t->name);  
 printf("\nDIESEASE:");  
 printf("%s",t->diesease);  
 printf("\nADDRESS");  
 printf("\nHOUSE.NO:");  
 printf("%d",(t->add.hno));  
 printf("\nSTREET.NO:");  
 printf("%d",(t->add.sno));  
 printf("\nCITY:");  
 printf("%s",(t->add.city));  
 t=t->link;  
 getch();  
 }  
 }  
 prior *delet(prior *f)  
 {  
 prior *nw;  
 queue *q,*q1;  
 q=f->front;  
 if(q->link==NULL)  
 {  
 nw=f;  
 f=f->next;  
 free(nw);  
 }  
 else  
 f->front=q->link;  
 free(q);  
 printf("\nDATA is DELETED!!!!!!");  
 getch();  
 return f;  
 }  
 prior *freeall(prior *f)  
 {  
 prior *t;  
 queue *s,*r;  
 while(f!=NULL)  
 {  
 r=f->front;  
 while(r!=NULL)  
 {  
 s=r;  
 r=r->link;  
 free(s);  
 }  
 t=f;  
 f=f->next;  
 free(t);  
 }  
 return f;  
 }