#include<cstdio>
#include <iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>

using namespace std;
typedef long long ll;
typedef pair<ll, ll> Pr;

string A, B;
map<char, int> m_a,m_b;

int main()
{
	cin >> A >> B;

	for (int i = 0; i < A.size(); i++) {
		m_a[A[i]]++;
		m_b[B[i]]++;
	}
	for (int i = 0; i < A.size(); i++) {
		if (m_a[A[i]] != m_b[A[i]] ||
			m_a[B[i]] != m_b[B[i]]) {
			cout << "NO" << endl;
			return 0;
		}
	}

	cout << "YES" << endl;
	return	0;
}