#include <bits/stdc++.h>
using namespace std;
int main() {
  string gname, rname, letters;
  cin >> gname;
  cin >> rname;
  cin >> letters;
  int c1 = 0, c2 = 0;
  bool match1 = false;
  bool match2 = false;
  if (letters.length() == (gname.length() + rname.length())) {
    for (int i = 0; i < gname.length(); i++)
      for (int j = 0; j < letters.length(); j++)
        if (gname[i] == letters[j]) {
          letters[j] = '/0';
          c1++;
          break;
        }
    if (c1 == gname.length()) match1 = true;
    for (int i = 0; i < rname.length(); i++)
      for (int j = 0; j < letters.length(); j++)
        if (rname[i] == letters[j]) {
          letters[j] = '/0';
          c2++;
          break;
        }
    if (c2 == rname.length()) match2 = true;
    if (match1 == true && match2 == true)
      cout << "YES";
    else
      cout << "NO";
  } else
    cout << "NO";
}
