#include <bits/stdc++.h>
using namespace std;
int main() {
  string a, b, c;
  cin >> a >> b >> c;
  int x[26] = {0}, y[26] = {0}, k = 0, i = 0;
  while (a[i] != NULL) {
    k = a[i];
    x[k - 65] += 1;
    i++;
  }
  i = 0;
  while (b[i] != NULL) {
    k = b[i];
    x[k - 65] += 1;
    i++;
  }
  i = 0;
  while (c[i] != NULL) {
    k = c[i];
    y[k - 65] += 1;
    i++;
  }
  for (i = 0; i < 26; i++) {
    if (x[i] != y[i]) {
      cout << "NO";
      break;
    }
  }
  if (i == 26) cout << "YES";
  return (0);
}
