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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#203815#7103. Red Black Treeucup-team484AC ✓524ms86780kbC++172.4kb2023-10-06 20:47:212023-10-06 20:47:21

Judging History

你现在查看的是最新测评结果

  • [2023-10-06 20:47:21]
  • 评测
  • 测评结果:AC
  • 用时:524ms
  • 内存:86780kb
  • [2023-10-06 20:47:21]
  • 提交

answer

#include <bits/stdc++.h>
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
#define st first
#define nd second
using namespace std;
typedef long long ll;
const int mod = 1e9 + 7;
const int N = 1e6 + 5;
const int LG = 17;
vector<pair<int, int>> adj[N];
ll cost[N];
int isr[N], idx[N], curc = 0;
int par[LG][N], dp[N];

int lca(int u, int v) {
	if (dp[u] < dp[v])
		swap(u, v);
	int d = dp[u] - dp[v];
	for (int i = 0; i < LG; i++)
		if (d >> i & 1)
			u = par[i][u];
	if (u == v)
		return u;
	for (int i = LG - 1; i >= 0; i--)
		if (par[i][u] != par[i][v])
			u = par[i][u], v = par[i][v];
	return par[0][u];
}

void dfs(int u, int p, ll d, int col) {
	if (isr[u])
		d = 0;
	if (p != -1 && isr[p])
		col = ++curc;
	if (p != -1) {
		dp[u] = dp[p] + 1;
		par[0][u] = p;
	}
	cost[u] = d;
	idx[u] = col;
	for (auto [v, w]: adj[u]) {
		if (v == p) continue;
		dfs(v, u, w + d, col);
	}
}

void solve() {
	int n, m, q; cin >> n >> m >> q;
	curc = 0;
	for (int i = 0; i < n; i++)
		adj[i].clear(), isr[i] = 0;
	for (int i = 0; i < m; i++) {
		int u; cin >> u; u--;
		isr[u] = 1;
	}
	for (int i = 1; i < n; i++) {
		int u, v, w; cin >> u >> v >> w;
		u--, v--;
		adj[u].push_back({v, w});
		adj[v].push_back({u, w});
	}
	dfs(0, -1, 0, 0);
	for (int i = 1; i < LG; i++) {
		for (int j = 0; j < n; j++)
			par[i][j] = par[i - 1][par[i - 1][j]];
	}
	while (q--) {
		int k; cin >> k;
		vector<int> arr(k);
		int bi = 0;
		for (int i = 0; i < k; i++) {
			int u; cin >> u; u--;
			if (cost[u] > cost[arr[bi]])
				bi = i;
			arr[i] = u;
		}
		ll ans = 0;
		vector<pair<ll, ll>> tmp;
		for (int i = 0; i < k; i++) {
			if (idx[arr[i]] != idx[arr[bi]])
				ans = max(ans, cost[arr[i]]);
			else {
				int l = lca(arr[bi], arr[i]);
				tmp.push_back({-cost[l], cost[arr[i]]});
//				cerr << arr[i]+1 << " " << arr[bi]+1 << " -> " << l+1 << " : " << cost[l] << endl;
			}
		}
		if (ans != cost[arr[bi]]) {
			sort(tmp.begin(), tmp.end());
			vector<ll> rem(sz(tmp) + 1);
			for (int i = sz(tmp) - 1; i >= 0; i--)
				rem[i] = max(rem[i + 1], tmp[i].second);
			ll val = cost[arr[bi]];
			for (int i = 0; val > ans && i < sz(tmp); i++)
				val = min(val, max(rem[i + 1], cost[arr[bi]] + tmp[i].first));
			ans = max(ans, val);
		}
		cout << ans << "\n";
	}
}

int main() {
	ios_base::sync_with_stdio(false); cin.tie(0);
	int t; cin >> t; while (t--) solve();
}

这程序好像有点Bug,我给组数据试试?

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 69040kb

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: 0
Accepted
time: 524ms
memory: 86780kb

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:

ok 577632 lines

Extra Test:

score: 0
Extra Test Passed