Submission #658901

#	Time	Username	Problem	Language	Result	Execution time	Memory
658901		JooDdae	산만한 고양이 (KOI17_cat)	C++17	100 / 100	500 ms	85960 KiB

cat

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

int n, m;

int in[300200], low[300200], cnt;
vector<int> v[300200];
stack<pair<int, int>> st;
vector<vector<pair<int, int>>> bcc;

int dfs(int u, int p){
    in[u] = low[u] = ++cnt;

    for(auto x : v[u]) if(x != p){
        if(in[u] > in[x]) st.push({u, x});

        if(in[x]) low[u] = min(low[u], in[x]);
        else{
            low[u] = min(low[u], dfs(x, u));
            if(low[x] >= in[u]){
                vector<pair<int, int>> b;
                while(st.top() != make_pair(u, x)) b.push_back(st.top()), st.pop();
                b.push_back(st.top()), st.pop();
                if(b.size() > 1) bcc.push_back(b);
            }
        }
    }

    return low[u];
}


int c[300300];

int main(){
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> m;
    for(int i=1;i<=m;i++) {
        int a, b; cin >> a >> b;
        v[a].push_back(b), v[b].push_back(a);
    }

    dfs(1, 0);

    for(auto b : bcc) {
        map<int, int> mp;
        for(auto [x, y] : b) mp[x]++, mp[y]++;
        for(auto [x, y] : mp) if((int)b.size() - y <= (int)mp.size() - 2)
            // cout << x << " " << y << "\n";
            c[x]++;
    }

    ll ans = 0;
    for(int i=1;i<=n;i++) if(m-(int)v[i].size() <= n-2 && (bcc.empty() || c[i] == bcc.size())) ans += i;
    cout << ans;
}

Compilation message (stderr)

cat.cpp: In function 'int main()':
cat.cpp:55:80: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |     for(int i=1;i<=n;i++) if(m-(int)v[i].size() <= n-2 && (bcc.empty() || c[i] == bcc.size())) ans += i;
      |                                                                           ~~~~~^~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 10 / 10
• Subtask 3: 23 / 23
• Subtask 4: 55 / 55