#define ll long long #define fo(i , n) for(ll i = 0 ; i < n ; i++) #include<bits/stdc++.h> using namespace std ; void solve() { ll n ; cin >> n ; string a , b ; cin >> a >> b ; if(a == b) { cout << "YES\n" ; return ; } int flag = 0 ; for(int i = 0 ; i < n-1 ; i++) { if(a[i] == a[i+1]) flag |= 1 ; if(b[i] == b[i+1]) flag |= 2 ; } sort(a.begin() , a.end()) ; sort(b.begin() , b.end()) ; if(a == b && flag == 3) cout << "YES\n" ; else cout << "NO\n" ; return ; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); #ifndef ONLINE_JUDGE freopen("inputf.txt" , "r" , stdin) ; freopen("outputf.txt" , "w" , stdout) ; freopen("error.txt" , "w" , stderr) ; #endif ll t = 1 ; cin >> t ; while(t--) { solve() ; } cerr << "Time : " << 1000 * ((double)clock()) / (double)CLOCKS_PER_SEC << "ms\n"; return 0; }