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https://git.sb/baoshuo/OI-codes.git
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60 lines
1.0 KiB
C++
60 lines
1.0 KiB
C++
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#include <iostream>
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#include <algorithm>
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#include <compare>
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#include <limits>
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#include <vector>
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using std::cin;
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using std::cout;
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const char endl = '\n';
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const int N = 1505;
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int n, a[N], f[N][3];
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std::vector<int> g[N];
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void dfs(int u, int fa) {
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f[u][2] = a[u];
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for (int v : g[u]) {
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if (v == fa) continue;
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dfs(v, u);
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f[u][0] += std::min(f[v][1], f[v][2]);
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f[u][2] += std::min({f[v][0], f[v][1], f[v][2]});
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}
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f[u][1] = std::numeric_limits<int>::max();
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for (int v : g[u]) {
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if (v == fa) continue;
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f[u][1] = std::min(f[u][1], f[u][0] - std::min(f[v][1], f[v][2]) + f[v][2]);
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}
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}
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int main() {
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std::ios::sync_with_stdio(false);
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cin.tie(nullptr);
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cin >> n;
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for (int i = 1, u, v, m; i <= n; i++) {
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cin >> u >> a[u] >> m;
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while (m--) {
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cin >> v;
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g[u].emplace_back(v);
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g[v].emplace_back(u);
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}
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}
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dfs(1, 0);
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cout << std::min(f[1][1], f[1][2]) << endl;
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return 0;
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}
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