#include <stdio.h>

char *StringChar(char *s, const char a[]) {
	int i;
	
	for(i = 0; i < 3; i++) {
		while (*s != a[i] && *s != '\0')
			s++;
	}
	if (*s == '\0')
		return (NULL);
	else
		return (s);
}

void main(void) {
	char *p;
	char a[] = {'a', 'b', 'c'};
	char str[ ] = "abcdefghijklmnopqrstuvwxyz";
	
	printf("str = %s\n", str);
	
	p = StringChar(str, a);
	printf("\nThe string after the search character is\n");
	if (p != NULL)
		printf("%s\n\n", p);
	else
		printf("can not find!\n");
}