#include<cstdio>
#include<iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>
#include<limits>

#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()

using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ll, string> pls;

int main()
{
	vector<int> d(7);
	for (int i = 0; i < 7; i++)
		cin >> d[i];

	sort(d.begin(), d.end());
	do {
		int D[7] = { 0 }, j = 0;
		bool flag = true;
		for (auto x : d) {
			D[j++] = x;
		}

		for (int i = 1; i < 6; i++) {
			int mi = min(D[i], min(D[i - 1], D[i + 1]));
			int mx = max(D[i],max(D[i-1],D[i+1]));
				if (!(((mi == D[i]) || (mx == D[i])) && (D[i + 1] > D[i - 1]))) {
					flag = false;
				}
				if (!(D[i - 1] != D[i + 1] && D[i + 1] != D[i] && D[i - 1] != D[i]))
					flag = false;
		}
		if (flag) {
			cout << "YES" << endl;
			return 0;
		}
	} while (next_permutation(d.begin(), d.end()));
	cout << "NO" << endl;
	return 0;
}