#include<bits/stdc++.h>
#include "diameter.h"
using namespace std;
/*check begin*/
#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <vector>
#include "diameter.h"
namespace {
static void WA(std::string err) {
	std::cout << "WA: " << err << std::endl;
	exit(0);
}

static const int N = 2e5 + 10;
static int subid, n;
static std::vector<int> e[N];

static int fa[N], dep[N], cnt, p[N], pos[N], l[N], r[N];
static void dfs(int u) {
	p[++cnt] = u, pos[u] = cnt;
	dep[u] = dep[fa[u]] + 1;
	l[u] = cnt;
	for (auto v : e[u])
		if (v != fa[u]) {
			fa[v] = u, dfs(v);
			p[++cnt] = u;
		}
	r[u] = cnt;
}

static int lg[N];
static std::pair<int, int> mn[N][20];
static void init() {
	cnt = 0, dfs(1), lg[0] = -1;
	for (int i = 1; i <= cnt; i++) {
		mn[i][0] = std::make_pair(dep[p[i]], p[i]);
		lg[i] = lg[i >> 1] + 1;
	}
	for (int j = 1; j <= lg[cnt]; j++) {
		for (int i = 1; i <= cnt - (1 << j) + 1; i++) {
			mn[i][j] = std::min(mn[i][j - 1], mn[i + (1 << (j - 1))][j - 1]);
		}
	}
}
static int LCA(int x, int y) {
	int l = pos[x], r = pos[y];
	if (l > r) std::swap(l, r);
	int tmp = lg[r - l + 1];
	return std::min(mn[l][tmp], mn[r - (1 << tmp) + 1][tmp]).second;
}

static int cntq2;
static int cntq1;

static int dis(int x, int y) { return dep[x] + dep[y] - 2 * dep[LCA(x, y)]; }

static void solve() {
	cntq1 = cntq2 = 0;
	scanf("%d", &n);
	for (int i = 1; i <= n; i++) e[i].clear();
	for (int i = 1; i < n; i++) {
		int x, y;
		scanf("%d%d", &x, &y);
		e[x].push_back(y);
		e[y].push_back(x);
	}
	init();
	std::pair<int, int> ans = find_diameter(subid, n);
	int x = 1, y = 1;
	for (int i = 1; i <= n; i++)
		if (dis(x, i) > dis(x, y)) y = i;
	x = y, y = 1;
	for (int i = 1; i <= n; i++)
		if (dis(x, i) > dis(x, y)) y = i;
	if (ans.first < 1 || ans.first > n) {
		WA("find wrong diameter!");
	}
	if (ans.second < 1 || ans.second > n) {
		WA("find wrong diameter!");
	}
	if (dis(x, y) != dis(ans.first, ans.second)) {
		WA("find wrong diameter!");
	}
}
}  // namespace
bool in(int x, int y, int z) {
	if (x < 1 || x > n) WA("ask2 format error");
	if (y < 1 || y > n) WA("ask2 format error");
	if (z < 1 || z > n) WA("ask2 format error");
	++cntq2;
	if (cntq2 > 2) {
		WA("too many ask2");
	}
	int cnt = 0;
	if (pos[y] >= l[x] && pos[y] <= r[x]) ++cnt;
	if (pos[z] >= l[x] && pos[z] <= r[x]) ++cnt;
	if (cnt == 1) return 1;
	return LCA(y, z) == x;
}

int query(int x, int y, int z) {
	if (x == y || y == z || x == z) WA("ask1 format error");
	if (x < 1 || x > n) WA("ask1 format error");
	if (y < 1 || y > n) WA("ask1 format error");
	if (z < 1 || z > n) WA("ask1 format error");
	++cntq1;
	if (cntq1 > 300000) {
		WA("too many ask1");
	}
	return dis(x, y) + dis(x, z) + dis(y, z);
}
int main() {
	int T;
	scanf("%d%d", &subid, &T);
	while (T--) solve();
	puts("correct");
}
/*check end*/
int cal(int x,int y){
	int d=1e9;
	int _=0;
	for(int i=1;i<=n;i++){
		if(i==x||i==y)continue;
		int dd=query(x,y,i);
		if(dd<d){
			d=dd;
			_=i;
		}
	}
	if(!in(_,x,y))d=1;
	while(d>1){
		for(int i=1;i<=n;i++){
			if(i==x||i==y)continue;
			int dd=query(x,y,i);
			if(dd<=d){
				d=dd;
				y=i;
				break;
			}
		}
	}
	int mx=0;
	int u=y;
	for(int i=1;i<=n;i++){
		if(i==x||i==y)continue;
		int dd=query(i,x,y);
		if(dd>mx){
			mx=dd;
			u=i;
		}
	}
	return u;
}
std::pair<int, int> find_diameter(int subid, int n) {
	if(n==1)return make_pair(1,1);
	if(n==2)return make_pair(1,2);
	int u=cal(1,2);
	int v=cal(u,2);
	return make_pair(u,v);
}

answer.code: In function ‘int main()’:
answer.code:117:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  117 |         scanf("%d%d", &subid, &T);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~
answer.code: In function ‘void {anonymous}::solve()’:
answer.code:62:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   62 |         scanf("%d", &n);
      |         ~~~~~^~~~~~~~~~
answer.code:66:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   66 |                 scanf("%d%d", &x, &y);
      |                 ~~~~~^~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccQunyk2.o: in function `in(int, int, int)':
answer.code:(.text+0x340): multiple definition of `in(int, int, int)'; /tmp/ccsbUY1q.o:implementer.cpp:(.text+0x470): first defined here
/usr/bin/ld: /tmp/ccQunyk2.o: in function `query(int, int, int)':
answer.code:(.text+0x530): multiple definition of `query(int, int, int)'; /tmp/ccsbUY1q.o:implementer.cpp:(.text+0x650): first defined here
/usr/bin/ld: /tmp/ccQunyk2.o: in function `main':
answer.code:(.text.startup+0x0): multiple definition of `main'; /tmp/ccsbUY1q.o:implementer.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status