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35 lines
609 B
C++
35 lines
609 B
C++
#include <bits/stdc++.h>
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using namespace std;
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vector<int> l[100010];
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int n, m, f, s, ans, pd[100010];
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void dfs(int x) {
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for (int y = 0; y < l[x].size(); y++) {
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if (!pd[l[x][y]]) {
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pd[l[x][y]] = 1;
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dfs(l[x][y]);
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}
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}
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}
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int main() {
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int p, q;
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cin >> n >> m;
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for (int i = 1; i <= m; i++) {
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cin >> p >> q;
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l[p].push_back(q);
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l[q].push_back(p);
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}
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for (int i = 1; i <= n; i++) {
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if (!pd[i]) {
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ans++;
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pd[i] = 1;
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dfs(i);
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}
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}
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cout << ans << endl;
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return 0;
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}
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