#include <stdio.h>

char s[27];
int a[26] = {0, 0, 0, 0, 3, 0, 5, 0, 7, 7, 7, 0, 11, 0, 13, 7, 7, 0, 8, 0, 19, 19, 7, 0, 23, 23};

int main(void) {
	s[0] = '0'; scanf("%s", s + 1);
	int i = 0; while(s[i + 1] != '\0') { i++; }
	int v, n = (s[i-1] - '0') * 10 + (s[i] - '0');
	if(i <= 2 && n <= 25) { v = a[n]; } else { v = 8; }
	printf("%d\n", v);
	return 0;
}