Write the function any(s1, s2), which returns the first location in the string s1 where any character from the string s2 occurs, or -1 if s1 contains no characters from s2. (The standard library function strpbrk does the same job but returns a pointer to the location.)

/* any:return first location in s1 where any char from s2 occurs */
int any(char s1[], char s2[]){
     int i, j;
     for(i =0; s1[i] != '\0'; i++)
        for (j=0; s2[j] != '\0'; j++)
            if(s1[i] == s2[j]  /* match found?   */
                return i;
     return -1;
}