#include <stdio.h>

int main(){
	int n[3];
	int count = 0;
	for (int i = 0; i < 3; i++) {
		scanf("%d", &n[i]);//_s
	}
	if (n[0] != 7 && n[1] != 7 && n[2] != 7) {
		printf("no");
	}
	else
		printf("yes");
}