#include <bits/stdc++.h>
using namespace std;
int main() {
  int cnt[26] = {};
  string a, b, c;
  cin >> a >> b >> c;
  for (int i = 0; i < a.size(); cnt[a[i++] - 'A']++)
    ;
  for (int i = 0; i < b.size(); cnt[b[i++] - 'A']++)
    ;
  for (int i = 0; i < c.size(); cnt[c[i++] - 'A']--)
    ;
  for (int i = 0; i < 26; i++) {
    if (cnt[i]) {
      cout << "NO\n";
      return 0;
    }
  }
  cout << "YES\n";
}
