#include <bits/stdc++.h>
using namespace std;
void fileIO() {}
bool sortbysecdesc(const pair<long long, long long> &a,
                   const pair<long long, long long> &b) {
  return a.second > b.second;
}
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  fileIO();
  long long T;
  T = 1;
  while (T--) {
    string s1, s2, s3;
    cin >> s1 >> s2 >> s3;
    long long alpha[26];
    fill(alpha, alpha + 26, 0);
    for (long long i = 0; i < s1.size(); i++) alpha[s1[i] - 'A']++;
    for (long long i = 0; i < s2.size(); i++) alpha[s2[i] - 'A']++;
    for (long long i = 0; i < s3.size(); i++) alpha[s3[i] - 'A']--;
    string ans = "YES";
    for (long long i = 0; i < 26; i++) {
      if (alpha[i] != 0) {
        ans = "NO";
        break;
      }
    }
    cout << ans;
  }
  return 0;
}
