1 /*
2  * 2-5. Write the function any(s1,s2), which returns the first location in
3  * the string s1 where any character from the string s2 occurs, or -1 if s1
4  * contains no characters from s2. (The standard library function strpbrk
5  * does the same job but returns a pointer to the location.)
6  */
7 #include <stdio.h>
8 
9 int any(char s1[], char s2[]);
10 int strchr(const char *s, int c);
11 
12 main () {
13 	printf("2: %d\n", any("The quick brown fox jumped over the lazy dog.", "aeiou"));
14 	printf("5: %d\n", any("The quick brown fox jumped over the lazy dog.", "aiou"));
15 	printf("6: %d\n", any("The quick brown fox jumped over the lazy dog.", "aio"));
16 	printf("12: %d\n", any("The quick brown fox jumped over the lazy dog.", "ao"));
17 }
18 
19 int any(char s1[], char s2[]) {
20 	int ret;
21 	for (int i = 0; s1[i] != '\0'; ++i)
22 		if (strchr(s2,s1[i]))
23 			return i;
24 	return -1;
25 }
26 int strchr(const char *s, int c) {
27 	int i;
28 	for (i = 0; *(s+i) != c; ++i)
29 		if (*(s+i) == '\0')
30 			return 0;
31 	return i;
32 }