#include <bits/stdc++.h>
using namespace std;
int main() {
  string s1;
  cin >> s1;
  string s2;
  cin >> s2;
  string s3;
  cin >> s3;
  int x = 0;
  int freq[26] = {0};
  for (int i = 0; i < s1.length(); i++) {
    freq[s1[i] - 'A']++;
  }
  for (int i = 0; i < s2.length(); i++) {
    freq[s2[i] - 'A']++;
  }
  for (int i = 0; i < s3.length(); i++) {
    freq[s3[i] - 'A']--;
  }
  for (int i = 0; i < 26; i++) {
    if (freq[i] != 0) {
      x = 1;
      cout << "NO" << endl;
      break;
    }
  }
  if (x == 0) {
    cout << "YES" << endl;
  }
  return 0;
}
