Program to compare two strings without using library function strcmp

Program to compare two strings without using library function strcmp

#include<stdio.h>

#include<string.h>

void main()

{

       int len1, len2, flag = 0, i;

      char s1[20], s2[20];

      printf("\nEnter s1: ");

      gets(s1);

      printf("\nEnter s2: ");

      gets(s2);

      len1 = strlen(s1);

      len2 = strlen(s2);

      if(len1 != len2)

      {

             flag = 1;

      }

     else

     {

            for(i=0;i<len1;i++)

           { 

                 if(s1[i] != s2[i])

                {

                       flag = 1;

                       break;

                 }

          }

    }

    if(flag == 0)

        printf("\nStrings are same.");

    else

        printf("\nStrings are different.");

}

Output:

Case 1:

Enter s1: abcde

Enter s2: abcdef

Strings are different.

Case 2:

Enter s1: abcde

Enter s2: abfgh

Strings are different.

Case 3:

Enter s1: abcde

Enter s2: abcde

Strings are same.