#include <bits/stdc++.h>
using namespace std;
int nand(int a, int b){
  return 1 - (a & b);
}
int main(){
  vector<string> A(6);
  for (int i = 0; i < 6; i++){
    cin >> A[i];
  }
  vector<string> A2 = A;
  sort(A2.begin(), A2.end());
  A2.erase(unique(A2.begin(), A2.end()), A2.end());
  int cnt = A2.size();
  vector<int> B(6);
  for (int i = 0; i < 6; i++){
    B[i] = lower_bound(A2.begin(), A2.end(), A[i]) - A2.begin();
  }
  bool ok = false;
  for (int i = 0; i < (1 << cnt); i++){
    vector<int> p(cnt);
    for (int j = 0; j < cnt; j++){
      p[j] = i >> j & 1;
    }
    if (nand(nand(nand(p[B[0]], p[B[1]]), p[B[2]]), nand(nand(p[B[3]], p[B[4]]), p[B[5]]))){
      ok = true;
    }
  }
  if (ok){
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
  }
}