#include <stdio.h>

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