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63 lines
1.2 KiB
C++
63 lines
1.2 KiB
C++
#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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using std::endl;
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const int N = 20005;
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int n, m, x, y;
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std::vector<int> ans, g[N];
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// Tarjan
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int cnt, dfn[N], low[N];
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int root;
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bool cut[N];
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void tarjan(int u) {
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dfn[u] = low[u] = ++cnt;
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bool flag = false;
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for (int v : g[u]) {
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if (!dfn[v]) {
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tarjan(v);
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low[u] = std::min(low[u], low[v]);
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if (dfn[u] <= low[v]) {
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if (u != root || flag) {
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cut[u] = true;
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} else {
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flag = true;
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}
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}
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} else {
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low[u] = std::min(low[u], dfn[v]);
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}
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}
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}
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int main() {
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cin >> n >> m;
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for (int i = 1; i <= m; i++) {
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cin >> x >> y;
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g[x].push_back(y);
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g[y].push_back(x);
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}
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for (int i = 1; i <= n; i++) {
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if (!dfn[i]) {
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root = i;
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tarjan(i);
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}
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}
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for (int i = 1; i <= n; i++) {
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if (cut[i]) {
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ans.push_back(i);
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}
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}
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cout << ans.size() << endl;
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for (int i : ans) {
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cout << i << ' ';
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}
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cout << endl;
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return 0;
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}
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