#include <bits/stdc++.h>
using namespace std;
int main(int argc, char** argv) {
  string ar1, ar2, ar3;
  int str1[26] = {0}, str2[26] = {0};
  int count = 0, i, m, n, x;
  getline(cin, ar1);
  getline(cin, ar2);
  getline(cin, ar3);
  ar1.append(ar2);
  m = ar1.size();
  x = ar3.size();
  for (i = 0; i < m; i++) {
    str1[ar1[i] - 'A']++;
  }
  for (i = 0; i < x; i++) {
    str2[ar3[i] - 'A']++;
  }
  for (i = 0; i < 26; i++) {
    if (str1[i] != str2[i]) {
      count = 1;
      break;
    }
  }
  if (count == 0)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
