/* * strspn - find length of initial segment of s consisting entirely * of characters from accept */#include <string.h>size_tstrspn(const char *s1, const char *s2){	register const char *sscan;	register const char *ascan;	register size_t count;	count = 0;	for (sscan = s1; *sscan != '\0'; sscan++) {		for (ascan = s2; *ascan != '\0'; ascan++)			if (*sscan == *ascan)				break;		if (*ascan == '\0')			return count;		count++;	}	return count;}