#include <bits/stdc++.h>
using namespace std;
int main() {
  string x, y, z;
  int a = 0, c = 0;
  cin >> x;
  cin >> y;
  cin >> z;
  for (int i = 0; i < x.length(); i++) {
    for (int j = 0; j < z.length(); j++) {
      if (x[i] == z[j]) {
        c += 1;
        z[j] = '1';
        break;
      }
    }
  }
  for (int i = 0; i < y.length(); i++) {
    for (int j = 0; j < z.length(); j++) {
      if (y[i] == z[j]) {
        a += 1;
        z[j] = '1';
        break;
      }
    }
  }
  if (c + a == z.length() && a == y.length() && c == x.length())
    cout << "YES";
  else
    cout << "NO";
}
