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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#160962#7103. Red Black Treeucup-team004#AC ✓783ms23348kbC++202.6kb2023-09-02 21:57:112023-09-02 21:57:12

Judging History

你现在查看的是最新测评结果

  • [2023-09-02 21:57:12]
  • 评测
  • 测评结果:AC
  • 用时:783ms
  • 内存:23348kb
  • [2023-09-02 21:57:11]
  • 提交

answer

#include <bits/stdc++.h>

using i64 = long long;

void solve() {
    int n, m, q;
    std::cin >> n >> m >> q;
    
    std::vector<i64> c(n, 1E18);
    for (int i = 0; i < m; i++) {
        int x;
        std::cin >> x;
        x--;
        c[x] = 0;
    }
    
    std::vector<i64> dep(n);
    std::vector<int> in(n);
    std::vector<std::vector<std::pair<int, int>>> adj(n);
    for (int i = 1; i < n; i++) {
        int u, v, w;
        std::cin >> u >> v >> w;
        u--, v--;
        adj[u].emplace_back(v, w);
        adj[v].emplace_back(u, w);
    }
    std::vector<int> parent(n);
    parent[0] = -1;
    int cur = 0;
    
    const int logn = std::__lg(n);
    std::vector a(logn + 1, std::vector<int>(n - 1));
    auto dfs = [&](auto self, int x) -> void {
        in[x] = cur++;
        if (cur > 1) {
            a[0][cur - 2] = parent[x];
        }
        for (auto [y, w] : adj[x]) {
            if (y == parent[x]) {
                continue;
            }
            parent[y] = x;
            dep[y] = dep[x] + w;
            c[y] = std::min(c[y], c[x] + w);
            self(self, y);
        }
    };
    dfs(dfs, 0);
    
    for (int j = 0; j < logn; j++) {
        for (int i = 0; i + (2 << j) <= n - 1; i++) {
            a[j + 1][i] = dep[a[j][i]] < dep[a[j][i + (1 << j)]] ? a[j][i] : a[j][i + (1 << j)];
        }
    }
    auto lca = [&](int x, int y) {
        if (x == y) {
            return x;
        }
        if (in[x] > in[y]) {
            std::swap(x, y);
        }
        int k = std::__lg(in[y] - in[x]);
        int u = a[k][in[x]];
        int v = a[k][in[y] - (1 << k)];
        return dep[u] < dep[v] ? u : v;
    };
    
    for (int _ = 0; _ < q; _++) {
        int k;
        std::cin >> k;
        
        std::vector<int> v(k);
        for (int i = 0; i < k; i++) {
            std::cin >> v[i];
            v[i]--;
        }
        std::sort(v.begin(), v.end(),
            [&](int i, int j) {
                return c[i] < c[j];
            });
        i64 ans = c[v[k - 1]];
        int l = v[k - 1];
        i64 maxdep = dep[v[k - 1]];
        for (int i = k - 1; i >= 0; i--) {
            maxdep = std::max(maxdep, dep[v[i]]);
            l = lca(l, v[i]);
            ans = std::min(ans, std::max((i ? c[v[i - 1]] : 0LL), maxdep - dep[l]));
        }
        std::cout << ans << "\n";
    }
}

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

这程序好像有点Bug,我给组数据试试?

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 3540kb

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: 783ms
memory: 23348kb

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