#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

using namespace std;

int main() {


  string a,b;
  vector<char> v,w;
  cin >> a >> b;
  int c = a.size();
  for (int i = 0; i < c; i++) {
    v.push_back(a[i]);
    w.push_back(b[i]);

  }
  sort(v.begin(),v.end());
  sort(w.begin(),w.end());

  if (v == w) {
    cout << "YES" << "\n";
  }else{
    cout << "NO" << "\n";
  }

  return 0;
}