#include <bits/stdc++.h>
using namespace std;
int main() {
  string str1, str2, str3;
  cin >> str1 >> str2 >> str3;
  int arr[26] = {0};
  for (int i = 0; i < str1.size(); i++) {
    arr[str1[i] - 'A']++;
  }
  for (int i = 0; i < str2.size(); i++) {
    arr[str2[i] - 'A']++;
  }
  for (int i = 0; i < str3.size(); i++) {
    arr[str3[i] - 'A']--;
  }
  for (int i = 0; i < 26; i++) {
    if (arr[i] == 0) {
      continue;
    } else {
      cout << "NO";
      return 0;
    }
  }
  cout << "YES" << endl;
  return 0;
}
