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

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

#define FOR(i,a,b) for(ll i=(a);i<(b);++i)
#define ALL(v) (v).begin(), (v).end()
#define p(s) cout<<(s)<<endl
#define p2(s, t) cout << (s) << " " << (t) << endl
#define br() p("")
#define pn(s) cout << (#s) << " " << (s) << endl
#define p_yes() p("YES")
#define p_no() p("NO")

bool is_kadomatsu(ll a, ll b, ll c){
    if(a==b || b==c || a==c){
        return false;
    }
    ll diff0 = b-a;
    ll diff1 = c-b;
    if(diff0*diff1<0){
        return true;
    }else{
        return false;
    }
}

bool check(vector<ll> &A){
    ll L = A.size();
    FOR(i, 0, L-2){
        if(!is_kadomatsu(A[i], A[i+1], A[i+2])) return false;
        if(A[i]>=A[i+2]) return false;
    }
    return true;
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);

    // input
    vector<ll> A(7);
    FOR(i, 0, 7){
        cin >> A.at(i);
    }
    sort(ALL(A));

    do{
        if(check(A)){
            p_yes();
            return 0;
        }
    }while(next_permutation(ALL(A)));
    
    p_no();

    return 0;
}