C code to find a string

strStr: c code for user defined function to find a string from multiple strings
#include<stdio.h>

int compare_string(char*, char*);

int main()
{
    char first[100], second[100], result;

    printf("Enter first string\n");
    gets(first);

    printf("Enter second string\n");
    gets(second);

    result = compare_string(first, second);

    if ( result == 0 )
       printf("Both strings are same.\n");
    else
       printf("Entered strings are not equal.\n");

    return 0;
}

int compare_string(char *first, char *second)
{
   while(*first==*second)
   {
      if ( *first == '\0' || *second == '\0' )
         break;

      first++;
      second++;
   }
   if( *first == '\0' && *second == '\0' )
      return 0;
   else
      return -1;
}

/*
OUTPUT:
-bash-3.2$ vi strStr.c
-bash-3.2$ gcc strStr.c
/tmp/ccUUzk8E.o: In function `main':
strStr.c:(.text+0x27): warning: the `gets' function is dangerous and should not be used.
-bash-3.2$ ./a.out
Enter few strings:
all is well
Enter the string to search:
code
NOT Present
-bash-3.2$ ./a.out
Enter few strings:
all is well
Enter the string to search:
all
Present at location :1
-bash-3.2$ ./a.out
Enter few strings:
all is well
Enter the string to search:
is
Present at location :5
-bash-3.2$ ./a.out
Enter few strings:
all is well
Enter the string to search:
well
Present at location :8
-bash-3.2$ ./a.out
Enter few strings:
all is well
Enter the string to search:
ll
Present at location :2
-bash-3.2$
*/
//Alternatestrstr:String search return location

#include<stdio.h>

int strStrLocation(char *str1, char *str2);

int main()

{

char str1[20];

char str2[20];

printf("Enter String1:\n");

gets(str1);

printf("Enter String2:\n");

gets(str2);

int r=0;

r=strStrLocation(str1,str2);

if(r!=-1)printf("found at %d\n",r+1);

else printf("Not found\n");

return 0;

}

int strStrLocation(char *str11, char *str22)

{

char *str1;

char *str2;

str1=str11;

str2=str22;

int location=0;

while(*str11)

{

while(*str1==*str2)

{

str1++;

str2++;

if(*str1=='\0'||*str2=='\0') break;

}

if(*str2=='\0')

break;

str11++; location++;

str1=str11;

str2=str22;

}//first while

if(*str11)

{

printf("%c\n",*str11);

return location;

}

else

return -1;

}

/*

Enter String1:

india

Enter String2:

ind

i

found at 1

-bash-3.2$ ./a.out

Enter String1:

ind

Enter String2:

india

Not found

-bash-3.2$ ./a.out

Enter String1:

india is grt

Enter String2:

grt

g

found at 10

*/