#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,tune=native")
#pragma GCC optimize("unroll-loops")
using namespace std;
const int inf = 1e9 + 123;
const long long ll_inf = 1e18 + 123;
const double eps = 1e-9;
const double PI = 3.141592653589793238462643;
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  string a, b, c;
  cin >> a >> b >> c;
  map<char, int> mp, mp2;
  for (char now : a) ++mp[now];
  for (char now : b) ++mp[now];
  for (char now : c) ++mp2[now];
  cout << (mp == mp2 ? "YES" : "NO");
  return 0;
}
