// No.69 文字を自由に並び替え
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int main() {
    string A, B;
    cin >> A >> B;
    sort(A.begin(), A.end());
    sort(B.begin(), B.end());
    if (A == B) cout << "YES" << endl;
    else cout << "NO" << endl;
}