#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
using namespace std;

bool checkKadomatsu(const vector<int>& a)
{
    if(a[0] >= a[2])
        return false;
    return (a[0] < a[1] && a[2] < a[1]) || (a[0] > a[1] && a[2] > a[1]);
}

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

    do{
        bool ok = true;
        for(int i=0; i<7-2; ++i){
            if(!checkKadomatsu(vector<int>(a.begin()+i, a.begin()+i+3)))
                ok = false;
        }
        if(ok){
            cout << "YES" << endl;
            return 0;
        }
    }while(next_permutation(a.begin(), a.end()));

    cout << "NO" << endl;
    return 0;
}