#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
const int N = 1000005;

int z, i, n, ok, tab[N], bat[N], diff;
string s1, s2;

int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);

cin >> z;
while(z--) {
	cin >> n >> s1 >> s2;
	for (i=0;i<n;i++) tab[i] = (s1[i] == '1');
	for (i=0;i<n;i++) bat[i] = (s2[i] == '1');
	ok = 0;
	for (i=1;i<n;i++) if (bat[i] != bat[i - 1]) ok = 1;
	diff = 0;
	for (i=0;i<n;i++) if (tab[i] != bat[i]) diff = 1;
	if (ok || !diff) cout << "YES\n"; else cout << "NO\n";
}
return 0;
}