#include <iostream>
#include <map>
#include <string>
using namespace std;

int main() {
    string a, b;
    cin >> a >> b;
    map<char,int> ma, mb;
    for (int i = 0; i < a.size(); i++) {
        ma[a[i]]++;
        mb[b[i]]++;
    }
    if (ma == mb)
        cout << "YES" << endl;
    else
        cout << "NO" << endl;
    return 0;
}