#include<stdio.h>
#include<conio.h>
    void main()
    {
        char a[21],b[21];
        int a1,n1,n2,j;
        int i;
        clrscr();
        printf("\n Please Give The STRING OF A : ");
        scanf("%s",a);    
        flushall();
        printf("\n Please Give The STRING TO B : ");
        scanf("%s",b);

        for(i=0,n1=0;a[i]!='\0';i++)
            n1++;
        for(i=0,n2=0;b[i]!='\0';i++)
        n2++;


        if(n1 < n2)
        {
          for(i=0;i<n2;i++)
                 {
            if(a[i]==b[i])
            j=0;
          else
          {
            a1=a[i]-b[i];
            printf(" THE DIFFERENCE BETWEEN IS HERE %d",a1);
            j++;
            break;
               }
      }
    }
    else
    {
     for(i=0;i<n1;i++)
     {
        if(a[i]==b[i])
            j=0;
        else
        {
            a1=a[i]-b[i];
            printf(" THE DIFFERENCE BETWEEN IS HERE %d",a1);
            j++;
            break;
        }
      }
     }

       if(j==0)
        printf(" BOTH ARE EQUALS");


       getch();
    }


************************ OUTPUT ************************************************

     Please Give The STRING OF A : MCA008

     Please Give The STRING TO B : MCA001

     THE DIFFERENCE BETWEEN IS HERE -42

********************************************************************************