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

int main() {
	int t;
	cin >> t;
    cin.ignore(numeric_limits<streamsize>::max(), '\n');
	while(t--) {
		string s1, s2;
		getline(cin, s1);
		getline(cin, s2);
		int s1_sz = s1.size();
		int s2_sz = s2.size();

		if(s1_sz != s2_sz) {
			cout << "NO\n";
			continue;
		}

		if(!s1.compare(s2)) {
			cout << "YES\n";
			continue;
		}

		if(s1_sz % 2 != 0) {
			cout << "NO\n";
			continue;
		}

		int mid = s1_sz / 2;

		if(!s1.substr(0, mid).compare(s2.substr(mid, s2_sz)) && !s2.substr(0, mid).compare(s1.substr(mid, s1_sz))) {
			cout << "YES\n";
		}
		else {
			cout << "NO\n";
		}
	}	
}