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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#179109#7103. Red Black Treenotyour_young#TL 0ms5972kbC++172.2kb2023-09-14 18:06:242023-09-14 18:06:24

Judging History

你现在查看的是最新测评结果

  • [2023-09-14 18:06:24]
  • 评测
  • 测评结果:TL
  • 用时:0ms
  • 内存:5972kb
  • [2023-09-14 18:06:24]
  • 提交

answer

#include<bits/stdc++.h>
#define endl '\n'
//#define int long long
using namespace std;
using  i64 = long long;
using PII = pair<int, int>;
const int N = 1e5+10;
int dfn[N], fa[N][18], dep[N], ti;
i64 dis[N], dr[N];
vector<PII> g[N];
bool red[N];

void dfs(int u, int father)
{
	dep[u] = dep[father] + 1;
	dfn[u] = ++ ti;
	fa[u][0] = father;
	for(int k = 1;k < 18;k ++)
		fa[u][k] = fa[fa[u][k - 1]][k - 1];
	
	if(red[u])
		dr[u] = 0;
	for(auto [v, w] : g[u])
	{
		if(v == father)
			continue;
		dis[v] = dis[u] + w;
		dr[v] = dr[u] + w;
		dfs(v, u);
	}
}

int lca(int a, int b)
{
	if(dep[a] < dep[b])
		swap(a, b);

	for(int k = 17;k >= 0;k --)
		if(dep[fa[a][k]] >= dep[b])
			a = fa[a][k];

	if(a == b)
		return a;

	for(int k = 17;k >= 0;k --)
		if(fa[a][k] != fa[b][k])
			a = fa[a][k], b = fa[b][k];

	return fa[a][0];
}
vector<int> v;
int k;

bool check(i64 x)
{
	vector<int> st;
	for(int u : v)
		if(dr[u] > x)
			st.push_back(u);
	 // sort(st.begin(), st.end(), [&](int a, int b){
	 // 	return dfn[a] < dfn[b];
	 // });

	if(st.size() <= 1)
		return true;

	int a = st[0], b = st[0];
	for(int u : st)
	{
		if(dfn[u] < dfn[a])
			a = u;
		if(dfn[u] > dfn[b])
			b = u;
	}

	int anc = lca(a, b);

	for(int u : st)
		if(dis[u] - dis[anc] > x)
			return false;
	return true;
}

void solve()
{
	int n, m, q;
	cin >> n >> m >> q;
	for(int i = 1, v;i <= m;i ++)
		cin >> v, red[v] = true;

	for(int i = 1;i < n;i ++)
	{
		int u, v, w;
		cin >> u >> v >> w;
		g[u].push_back({v, w});
		g[v].push_back({u, w});
	}
	dfs(1, 0);
	// for(int i = 1;i <= n;i ++)
	// 	cout << "u : " << i << ' ' << dr[i] << endl; 
	while(q --)
	{
		
		cin >> k;
		v.clear();
		for(int i = 1, u;i <= k;i ++)
			cin >> u, v.push_back(u);

		i64 l = 0, r = 1e15;
		while(l < r)
		{
			i64 mid = l + r >> 1;
			if(check(mid))
				r = mid;
			else
				l = mid  + 1;
		}

		cout << l << endl;
	}

	for(int i = 1;i <= n;i ++)
		for(int k = 0;k < 18;k ++)
			fa[i][k] = 0;
	ti = 0;
	for(int i = 1;i <= n;i ++)
		red[i] = false, g[i].clear();

}
int main()
{
	ios::sync_with_stdio(false), cin.tie(0);
	int tc;
	cin >> tc;
	while(tc --)
		solve();
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 5972kb

input:

2
12 2 4
1 9
1 2 1
2 3 4
3 4 3
3 5 2
2 6 2
6 7 1
6 8 2
2 9 5
9 10 2
9 11 3
1 12 10
3 3 7 8
4 4 5 7 8
4 7 8 10 11
3 4 5 12
3 2 3
1 2
1 2 1
1 3 1
1 1
2 1 2
3 1 2 3

output:

4
5
3
8
0
0
0

result:

ok 7 lines

Test #2:

score: -100
Time Limit Exceeded

input:

522
26 1 3
1
1 4 276455
18 6 49344056
18 25 58172365
19 9 12014251
2 1 15079181
17 1 50011746
8 9 2413085
23 24 23767115
22 2 26151339
26 21 50183935
17 14 16892041
9 26 53389093
1 20 62299200
24 18 56114328
11 2 50160143
6 26 14430542
16 7 32574577
3 16 59227555
3 15 8795685
4 12 5801074
5 20 57457...

output:

148616264
148616264
0
319801028
319801028
255904892
317070839
1265145897
1265145897
1072765445
667742619
455103436
285643094
285643094
285643094
317919339
0
785245841
691421476
605409472
479058444
371688030
303203698
493383271
919185207
910180170
919185207
121535083
181713164
181713164
181713164
181...

result: