Submission #3721183

---

Source Code Expand

#include <bits/stdc++.h>
using namespace std;

vector<int> g[110];
bool used[110];
bool dfs(int cur, int prev){
    if(used[cur]) return false;
    used[cur] = true;
    for(int i = 0; i < g[cur].size(); i++){
        if(g[cur][i] == prev) continue;
        if(!dfs(g[cur][i], cur)) return false;
    }
    return true;
}

int main(){
    int n, m;
    cin >> n >> m;
    for(int i = 0; i < m; i++){
        int u, v;
        cin >> u >> v;
        u--; v--;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    int sum = 0;
    for(int i = 0; i < n; i++){
        if(used[i]) continue;
        if(dfs(i, -1)) sum++;
    }
    cout << sum << endl;
    return 0;
}

Submission Info

Judge Result