// yukicoder
#include <bits/stdc++.h>
using namespace std;

int main()
{
    string s, t;
    cin >> s >> t;

    sort(s.begin(), s.end());
    sort(t.begin(), t.end());

    if(s == t) cout << "YES" << "\n";
    else cout << "NO" << "\n";

    return 0;
}