#include <bits/stdc++.h>
using namespace std;
int len(char* a) {
  int count;
  for (int i = 0; a[i] != '\0'; ++i) {
    ++count;
  }
  return count;
}
int main() {
  char a[101], b[101], c[101];
  int found = 0, i, j;
  fscanf(stdin, "%s%s%s", a, b, c);
  if (len(a) + len(b) != len(c)) {
    fprintf(stdout, "NO");
    return 0;
  }
  for (i = 0; c[i] != '\0'; ++i) {
    for (j = 0; a[j] != '\0'; ++j) {
      if (c[i] == a[j]) {
        found = 1;
        a[j] = 1;
        break;
      }
    }
    if (!found) {
      for (j = 0; b[j] != '\0'; ++j) {
        if (c[i] == b[j]) {
          found = 1;
          b[j] = 1;
          break;
        }
      }
    }
    if (!found) {
      fprintf(stdout, "NO");
      return 0;
    }
    found = 0;
  }
  fprintf(stdout, "YES");
  return 0;
}
