#include <iostream>
#include <algorithm>
using namespace std;

bool iskadomatsu(int a, int b, int c)
{
    return a!=c and ((b>a and b>c) or (b<a and b<c));
}

int main()
{
    vector<int> a(7);
    for(int& v: a) cin>>v;
    sort(begin(a), end(a));

    do {
        bool ok=true;
        for(int i=0; i<5; ++i) {
            if (!(a[i]<a[i+2] and iskadomatsu(a[i], a[i+1], a[i+2]))) {
                ok=false;
                break;
            }
        }
        if (ok) { cout<<"YES"<<endl; return 0; }
    } while (next_permutation(begin(a), end(a)));
    cout<<"NO"<<endl;
}