#include <bits/stdc++.h>
using namespace std;
char a[111], b[111], c[111];
int v1[26], v2[26];
int main() {
  scanf("%s%s%s", a, b, c);
  for (int i = 0; c[i] != '\0'; i++) v2[c[i] - 'A']++;
  for (int i = 0; a[i] != '\0'; i++) v1[a[i] - 'A']++;
  for (int i = 0; b[i] != '\0'; i++) v1[b[i] - 'A']++;
  for (int i = 0; i < 26; i++) {
    if (v2[i] != v1[i]) {
      printf("NO\n");
      return 0;
    }
  }
  printf("YES\n");
  return 0;
}
