Submission #1356235

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Source Code Expand

#include "bits/stdc++.h"
#include <regex>
#define _USE_MATH_DEFINES
#include <math.h>

using namespace std;

#ifndef _DEBUG
#define main_ main
#endif
#define FOR(i,s,e) for (int i = int(s); i < int(e); ++i)
#define REP(i,e) FOR(i,0,e)
#define INF (INT_MAX/2)
#define EPS (1.0e-8)
#define LINF (LONG_MAX/2)

typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<bool> vb;
typedef vector<string> vs;

template <typename T>
using keyVal = pair<string, T>;
template<typename T>
bool val_greater(const keyVal<T>& left, const keyVal<T>& right) {
	return left.second > right.second;
}

vs split(string str, char sep) {
	vs v; stringstream ss(str); string t;
	while (getline(ss, t, sep)) v.push_back(t);
	return v;
}

int N, M;
vvi E;
vb visited;

void dfs(int x) {
	visited[x] = true;
	FOR(i, 0, N) {
		if (E[x][i] == 0 || visited[i]) {
			continue;
		}
		dfs(i);
	}
}

int main_() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	cin >> N >> M;
	
	E.resize(N);
	FOR(i, 0, N) E[i].resize(N);
	FOR(i, 0, N)
		FOR(j, 0, N)
			E[i][j] = 0;

	visited.resize(N);
	FOR(i, 0, N) visited[i] = false;

	FOR(i, 0, M) {
		int a, b;
		cin >> a >> b;
		a--; b--;
		E[a][b] = E[b][a] = 1;
	}

	int cnt = 0;
	FOR(i, 0, N) {
		if (visited[i]) continue;
		dfs(i);
		cnt++;
	}

	int ans = cnt - 1;
	cout << ans << endl;

	return 0;
}

Submission Info

Judge Result