#include <bits/stdc++.h>
using namespace std;
int buf[26];
int main() {
  char c;
  while ((c = cin.get()) != 10) buf[c - 'A']++;
  while ((c = cin.get()) != 10) buf[c - 'A']++;
  while ((c = cin.get()) != 10) buf[c - 'A']--;
  if (count(buf, buf + 26, 0) == 26)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
