DataStructure Program to search for a string in another string

#include <stdio.h>
#include <conio.h>
#include <string.h>
int xstrsearch ( char *, char * ) ;
void show( ) ;
void main( )
{
char s1[ ] = "NagpurKicit" ;
char s2[ ] = "Kicit" ;
int pos ;
clrscr( ) ;
printf ( "String s1: %s\n", s1 ) ;
printf ( "String s2: %s\n", s2 ) ;
/* search if s2 is present in s1 */
pos = xstrsearch ( s1, s2 ) ;
printf ( "\nThe pattern string is found at position: %d\n", pos ) ;
getch( ) ;
}
/* searches for the given pattern s2 into the string s1 */
int xstrsearch ( char * s1, char * s2 )
{
int i, j, k ;
int l1 = strlen ( s1 ) ;
int l2 = strlen ( s2 ) ;
for ( i = 0 ; i <= l1 - l2 ; i++ )
{
j = 0 ;
k = i ;
while ( ( s1[k] == s2[j] ) && ( j < l2 ) )
{
k++ ;
j++ ;
}
if ( j == l2 )
return i ;
}
return -1 ;
}