제출 #1052621

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1052621		turska	Railway (BOI17_railway)	C++17	100 / 100	193 ms	45444 KiB

railway

#include <bits/stdc++.h>
using namespace std;
 
#define all(v) (v).begin(), (v).end()
 
int n, m, k;
vector<int> adj[100001];
vector<int> q[100001];
 
int z[100001];
 
vector<int> ans;
map<pair<int, int>, int> e;
 
map<int, int> dfs(int v, int p) {
    map<int, int> a;
 
    for (auto u: adj[v]) {
        if (u==p) continue;
        map<int, int> b = dfs(u, v);
 
        if (b.size()>=k) {
            ans.push_back(e[{v, u}]);
        }
 
        if (a.size() < b.size()) a.swap(b);
        for (auto [k, v]: b) {
            if (a[k]+v==z[k]) a.erase(k);
            else a[k] += v;
        }
    }
 
    for (auto u: q[v]) {
        a[u]++;
        if (a[u] == z[u]) a.erase(u);
    }
    return a;
}
 
int main() {
    cin >> n >> m >> k;
 
    for (int i=0; i<n-1; i++) {
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
        e[{u, v}] = i+1;
        e[{v, u}] = i+1;
    }
    for (int i=0; i<m; i++) {
        int s;
        cin >> s;
        z[i] = s;
        for (int j=0; j<s; j++) {
            int k;
            cin >> k;
            q[k].push_back(i);
        }
    }
    dfs(1, 1);
    sort(all(ans));
    cout << ans.size() << '\n';
    for (auto i: ans) cout << i << ' ';
}

컴파일 시 표준 에러 (stderr) 메시지

railway.cpp: In function 'std::map<int, int> dfs(int, int)':
railway.cpp:22:21: warning: comparison of integer expressions of different signedness: 'std::map<int, int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   22 |         if (b.size()>=k) {
      |             ~~~~~~~~^~~

• Subtask 1: 8 / 8
• Subtask 2: 15 / 15
• Subtask 3: 7 / 7
• Subtask 4: 29 / 29
• Subtask 5: 16 / 16
• Subtask 6: 25 / 25