#include <bits/stdc++.h>
using namespace std;

bool isKadomatsu(long long x, long long y, long long z) {
	if (x == y || y == z || x == z) return false;
	if (x > y && y < z && x < z) return true;
	if (x < y && y > z && x < z) return true;
	return false;
}

bool solve() {
	vector<int> a(7);
	for (int i = 0; i < 7; i++) {
		cin >> a[i];
	}
	sort(a.begin(), a.end());

	do {
		bool all = true;
		for (int i = 0; i < 5; i++) {
			all &= isKadomatsu(a[i], a[i + 1], a[i + 2]);
		}
		if (all) return true;
	} while (next_permutation(a.begin(), a.end()));

	return false;
}

int main() {
	cout << (solve() ? "YES" : "NO") << endl;
}