Text or Screen Editor in C++ Language

Write a program in C++ Language to implement a Text or Screen Editor which can edit the entered text on screen.Program should make a file which will be used for storing text .

Text or Screen Editor in C++ Language Code

 #include  
 #include  
 #include  
 #define left 21  
 #define top 7  
 #define right 59  
 #define bottom 24  
 void main()  
 {  
   clrscr();  
   window(left,top-1,right,bottom);  
   char buff[100][40];  
   FILE *fp;  
   fp=fopen("editfile.txt","w");  
   clrscr();  
   cprintf("F1 New F2 SAVE F3 OPEN F4 EXIT\n\r");  
   int x=wherex();  
   int y=wherey();  
   //gotoxy(x,y);  
   char ch;  
   int row;  
   int col;   
   int i;  
   do  
   {  
     flushall();  
     ch=getch();  
     int i=0,j=0;  
     if(ch==0)  
     {  
       ch=getch();  
     }  
     //int  
     char c;  
     switch(ch)  
     {  
       case '='://open  
         fp=fopen("editfile.txt","r");  
         i=0;  
         clrscr();  
         while(i<15)  
         {  
           c=fgetc(fp);  
           if(c=='\n')  
           {  
             i++;  
           }  
           cprintf("%c",c);  
         }  
         getch();  
       case '<':  
          //save  
         i=1;  
         fp=fopen("editfile.txt","w");  
         while(i<16)  
         {  
           j=1;  
           while( buff[i][j]!='~' && buff[i][j]!='\r')  
           {  
             fputc(buff[i][j],fp);  
             j++;  
           }  
           fputc('\n',fp);  
           i++;  
         }  
         fputc('\0',fp);  
         getch();  
         clrscr();  
         gotoxy(x,y);  
         cprintf("F1 New F2 SAVE F3 OPEN F4 EXIT\n\r");  
         break;  
       case ';': //NEW FILE  
         //cprintf("yo");  
         clrscr();  
         cprintf("F1 New F2 SAVE F3 OPEN F4 EXIT\n\r");  
         cprintf("NEW FILE CREATED\n\r");  
         row=1;  
         col=0;  
         i=0;  
         while(i<15)  
         {  
           strcpy(buff[i],NULL);  
           buff[i][0]='~';  
           buff[i][1]='~';  
           buff[i][2]=NULL;  
           i++;  
         }  
         break;  
       case '>'://exit t  
         break;  
       case '\r':// return character next line  
         row++;  
         col=0;  
         gotoxy(x+col,y+row);  
         break;  
       case 'P':  
         row++;  
         gotoxy(x+col,y+row);  
         break;  
       case 'H':  
         if(row!=1)  
         {  
           row--;  
           gotoxy(x+col,y+row);  
         }  
         break;  
        case 'M':  
         col++;  
         if(col==39)  
         {  
           col=0;  
           row++;  
         }  
         gotoxy(x+col,y+row);  
         break;  
        case 'K':  
         col--;  
         if(col==-1)  
         {  
           col=0;  
         }  
         gotoxy(x+col,y+row);  
         break;  
        case '\b':  
          if((col-1)==-1)  
          {  
           break;  
          }  
          if(buff[row][col+1]=='~')  
          {  
           buff[row][col]='~';  
           buff[row][col+1]=NULL;  
           gotoxy(x+col-1,y+row);  
           cprintf(" ");  
           gotoxy(x+col-1,y+row);  
           col--;  
          }  
         else  
          {  
           i=strlen(buff[row]);  
           j=col;  
           gotoxy(x+col-1,y+row);  
           while(j<=i)  
           {  
             buff[row][j]=buff[row][j+1];  
             if(buff[row][j+1]=='~')  
               break;  
             cprintf("%c",buff[row][j+1]);  
             j++;  
           }  
           cprintf(" ");  
           buff[row][i-1]=NULL;  
           gotoxy(x+col-1,y+row);  
           col--;  
          }  
         break;  
        case 'S':  
        if(buff[row][col+1]=='~')  
        {  
         buff[row][col]='~';  
         buff[row][col+1]=NULL;  
         gotoxy(x+col-1,y+row);  
         cprintf(" ");  
         gotoxy(x+col,y+row);  
        }  
        else  
        {  
         i=strlen(buff[row]);  
         j=col+1;  
         gotoxy(x+col,y+row);  
         while(j<=i)  
         {  
           buff[row][j]=buff[row][j+1];  
           if(buff[row][j+1]=='~')  
             break;  
           cprintf("%c",buff[row][j+1]);  
           j++;  
         }  
         cprintf(" ");  
         buff[row][i-1]=NULL;  
         gotoxy(x+col,y+row);  
        }  
         break;  
       default:  
         //row=where  
         col++;  
         if(col==39)  
         {  
           row++;  
           col=0;  
           gotoxy(x+col,y+row);  
         }  
         i=strlen(buff[row]);  
         if( (strlen(buff[row])-1)         {  
           for(i=strlen(buff[row])-1;i<col;++i) <br="">           {  
             buff[row][i]=' ';  
           }  
         }  
           //  else  
          //  col++;  
         buff[row][col+1]='~';  
         buff[row][col]=ch;  
         buff[row][col+2]=NULL;  
         cprintf("%c",ch);  
     }  
   }while(ch!='>');  
 }