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50 lines
1.1 KiB
50 lines
1.1 KiB
2 years ago
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#include <bits/stdc++.h>
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using namespace std;
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const int N = 1000010;
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#define int long long
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#define endl "\n"
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struct edge {
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int to, nxt;
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} e[N << 1];
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int n, cnt, id;
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int head[N];
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int ans;
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int f[N], dep[N], size[N];
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inline void add(int u, int v) {
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e[++cnt].nxt = head[u];
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head[u] = cnt;
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e[cnt].to = v;
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}
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void dfs1(int x, int fa) {
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size[x] = 1;
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dep[x] = dep[fa] + 1;
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for (int i = head[x]; i; i = e[i].nxt) {
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int y = e[i].to;
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if (y == fa) continue;
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dfs1(y, x);
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size[x] += size[y];
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}
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}
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void dfs2(int x, int fa) {
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for (int i = head[x]; i; i = e[i].nxt) {
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int y = e[i].to;
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if (y == fa) continue;
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f[y] = f[x] + n - 2 * size[y];
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dfs2(y, x);
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}
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}
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signed main() {
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cin >> n;
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for (int i = 1; i < n; i++) {
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int u, v;
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cin >> u >> v;
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add(u, v), add(v, u);
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}
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dfs1(1, 0);
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for (int i = 1; i <= n; i++) f[1] += dep[i];
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dfs2(1, 0);
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for (int i = 1; i <= n; i++)
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if (ans < f[i]) ans = f[i], id = i;
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cout << id << endl;
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}
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