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https://git.sb/baoshuo/OI-codes.git
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85 lines
1.3 KiB
C++
85 lines
1.3 KiB
C++
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#include <iostream>
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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 = 50005;
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int n, h[N], son[N], ans[N], res;
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std::vector<int> g[N];
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void dfs1(int u, int f) {
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for (int v : g[u]) {
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if (v == f) continue;
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dfs1(v, u);
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int x = std::min(h[u], h[v]);
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h[u] -= x, h[v] -= x;
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res += x * 2;
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if (h[v]) son[u] = v;
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}
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}
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void dfs2(int u, int f) {
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ans[u] = res;
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for (int v : g[u]) {
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if (v == f) continue;
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if (h[u]) {
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h[u]--, res++;
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dfs2(v, u);
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h[u]++, res--;
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} else if (son[v]) {
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h[son[v]]--, res++;
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dfs2(v, u);
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h[son[v]]++, res--;
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} else {
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h[v]++, res--;
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dfs2(v, u);
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h[v]--, res++;
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}
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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; i <= n; i++) {
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cin >> h[i];
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}
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for (int i = 1, x, y; i < n; i++) {
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cin >> x >> y;
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h[++x]--, h[++y]--;
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g[x].emplace_back(y);
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g[y].emplace_back(x);
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res += 2;
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}
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dfs1(1, 0);
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dfs2(1, 0);
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for (int i = 1; i <= n; i++) {
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cout << ans[i] << endl;
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}
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return 0;
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}
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