#include <bits/stdc++.h>
#define syosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> P;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<long double> vd;
typedef vector<vd> vvd;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<string> vs;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef vector<pll> vpll;
typedef pair<int,P> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const ll INF=1ll<<60;
const double pi=acos(-1);
const double eps=1e-8;
const ll mod=1e9+7;
const int dx[4]={0,1,0,-1},dy[4]={1,0,-1,0};

bool f(int x,int y,int z){
	return x!=y&&y!=z&&z>x&&(y<min(x,z)||y>max(x,z));
}

vi a(7);

int main(){
	a=vi(7);
	for(int i=0;i<7;i++) cin>>a[i];
	sort(a.begin(),a.end());
	bool B=0;
	do{
		bool b=1;
		for(int i=0;i<5;i++) b&=f(a[i],a[i+1],a[i+2]);
		B|=b;
	}while(next_permutation(a.begin(),a.end()));
	cout<<(B?"YES":"NO")<<endl;
}