/*
灏忓簾鐗╋紝杩欓兘涓嶄細 /cf
*/
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned ll 
#define mp make_pair
#define inf (ll)1e9
#define pii pair <ll, ll>
#define fr first
#define se second
const ll mod = 1e9 + 7;
char buf[1 << 21], *p1 = buf, *p2 = buf;
#define getchar() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 18, stdin), p1 == p2) ? EOF : *p1++)
inline ll read() {
	ll x = 0, f = 1;
	char ch = getchar();
	while(ch < '0' || ch > '9') f = ((ch == '-') ? -1 : f), ch = getchar();
	while(ch >= '0' && ch <= '9') x = x * 10 + ch - '0', ch = getchar();
	return x * f;
}
inline void write(ll x) {
	if(x < 0) x = -x, putchar('-');
	if(x >= 10) write(x / 10);
	putchar(x % 10 + '0');
}
ull bas, mv;
inline ull xorshift(ull x) {
	x ^= mv;
	x ^= x << 13;
	x ^= x >> 7;
	x ^= x << 17;
	x ^= mv;
	return x;
}
ll n;
vector <ll> G[100005];
inline ull dfs(ll x, ll fa) {
	ull now = bas;
	for(auto y : G[x]) {
		if(y == fa) continue;
		now += xorshift(dfs(y, x));
	}
	return now; 
}
int main() {
//	freopen(".in", "r", stdin);
//	freopen(".out", "w", stdout);
	srand(time(NULL));
	default_random_engine e(1ll * rand() * rand());
	uniform_int_distribution <ull> R(1, (1ull << 63) - 1);
	bas = R(e), mv = R(e);
	ll T = read();
	while(T--) {
		n = read();
		for(ll i = 1; i <= n; i++) G[i].clear();
		for(ll i = 1; i < n; i++) {
			ll u = read(), v = read();
			G[u].push_back(v);
			G[v].push_back(u);
		}
		ull ans = dfs(1, 0);
		for(ll i = 1; i <= n; i++) G[i].clear();
		for(ll i = 1; i < n; i++) {
			ll u = read(), v = read();
			G[u].push_back(v);
			G[v].push_back(u);
		}
		if(ans == dfs(1, 0)) puts("Isomorphism");
		else puts("No");
	}
	return 0;
}
/*
*/