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

int main(){
    vector<int> a(7);
    for(auto &&v:a)cin >> v;
    sort(a.begin(), a.end());
    auto f = [&](int i, int j, int k){
        if(a[i] == a[j] || a[j] == a[k] || a[k] == a[i])return false;
        return (a[i] < a[k]);
    };
    do{
        bool flag = true;
        for(int i = 0; i + 2 < 7; i++){
            if(!f(i, i + 1, i + 2))flag = false;
        }
        if(flag){
            cout << "YES" << '\n';
            return 0;
        }
    }while(next_permutation(a.begin(), a.end()));
    cout << "NO" << '\n';
}