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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#471456#9110. Zayin and Treereal_sigma_team#AC ✓220ms13644kbC++171.8kb2024-07-10 21:16:522024-07-10 21:16:53

Judging History

你现在查看的是最新测评结果

  • [2024-07-10 21:16:53]
  • 评测
  • 测评结果:AC
  • 用时:220ms
  • 内存:13644kb
  • [2024-07-10 21:16:52]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);

    int tests;
    cin >> tests;
    while (tests--) {
        int n;
        cin >> n;
        vector<int> a(n);
        for (auto& i : a) cin >> i;
        vector<vector<int>> g(n);
        for (int i = 0; i < n -1 ; ++i) {
            int u, v;
            cin >> u >> v;
            --u, --v;
            g[u].push_back(v);
            g[v].push_back(u);
        }
        vector<array<array<int, 2>, 2>> dp(n);
        int ans = 1;
        auto dfs = [&](auto dfs, int u, int p) -> void {
            for (int x = 0; x < 2; ++x) {
                for (int y = 0; y < 2; ++y) {
                    dp[u][x][y] = 1 + (x ? a[u] : 0) + (y ? -a[u] : 0);
                }
            }
            for (auto to : g[u]) {
                if (to == p) continue;
                dfs(dfs, to, u);
                for (int x = 0; x < 2; ++x) {
                    for (int y = 0; y < 2; ++y) {
                        ans = min(ans, dp[u][x][y] + dp[to][x ^ 1][y ^ 1]);
                    }
                }
                for (int x = 0; x < 2; ++x) {
                    for (int y = 0; y < 2; ++y) {
                        for (int i = 0; i < 2; ++i) {
                            for (int j = 0; j < 2; ++j) {
                                if (x & i) continue;
                                if (y & j) continue;
                                dp[u][x | i][y | j] = min(dp[u][x | i][y | j], dp[to][i][j] + 1 + (x ? a[u] : 0) + (y ? -a[u] : 0));
                            }
                        }
                    }
                }
            }
        };
        dfs(dfs, 0, -1);
        cout << ans << '\n';
    }
}

Details

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Test #1:

score: 100
Accepted
time: 220ms
memory: 13644kb

input:

3009
5
4 5 3 4 2
1 2
2 3
3 4
3 5
5
4 4 1 1 2
1 2
2 3
3 4
3 5
10
5 8 1 0 8 7 5 2 0 4
2 4
3 8
3 9
1 2
1 3
3 6
4 5
5 7
6 10
10
6 8 8 4 8 0 6 6 0 2
7 10
1 7
2 9
2 3
3 4
1 5
1 6
6 8
1 2
10
9 0 4 0 4 6 0 2 0 0
1 5
1 3
1 7
2 6
1 2
1 9
1 4
5 8
7 10
10
8 8 1 2 7 4 8 6 0 8
1 6
1 7
1 5
7 9
1 3
1 2
2 10
3 4
1 8...

output:

0
-1
-6
-6
-7
-6
-7
-4
-3
-7
-5
-6
-5
-4
-6
-3
-4
-7
-4
-4
-6
-6
-6
-5
-4
-5
-6
-6
-7
-7
-5
-7
-6
-6
-7
-6
-5
-5
-4
-6
-6
-5
-6
-6
-6
-6
-3
-6
-3
-6
-4
-6
-7
-6
-7
-6
-6
-5
-7
-6
-4
-7
-3
-5
-5
-6
-4
-5
-7
-6
-5
-5
-4
-3
-5
-3
-4
-2
-6
-5
-7
-4
-5
-5
-7
-7
-4
-6
-5
-4
-6
-5
-5
-6
-3
-6
-7
-7
-7
-6
-...

result:

ok 3009 lines