#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef complex<double> P;
typedef pair<int,int> pii;
#define REP(i,n) for(ll i=0;i<n;++i)
#define REPR(i,n) for(ll i=1;i<n;++i)
#define FOR(i,a,b) for(ll i=a;i<b;++i)

#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define DEBUG_VEC(v) cout<<#v<<":";REP(i,v.size())cout<<" "<<v[i];cout<<endl
#define ALL(a) (a).begin(),(a).end()

#define MOD (ll)(1e9+7)
#define ADD(a,b) a=((a)+(b))%MOD
#define FIX(a) ((a)%MOD+MOD)%MOD

bool isZ(int a,int b,int c){
  if(a==b || b==c || c==a)return false;
  if(a>=c)return false;
  return (b<a&&b<c)||(b>a&&b>c);
}

int main(){
  vi x(7);
  REP(i,7)scanf("%d",&x[i]);
  sort(ALL(x));
  bool flag = false;
  do{
    REP(i,5){
      if(isZ(x[i],x[i+1],x[i+2])){
        flag = true;
        break;
      }
    }
    if(flag)break;
  }while(next_permutation(ALL(x)));
  if(flag)puts("YES");
  else puts("NO");
  return 0;
}