BOJ 1766 문제집

1 개요

BOJ 1766 문제집

• 백준 온라인 저지 1766번 문제
• BOJ 42단계

2 C++

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

int N, M;
vector<int> node[32001];
int indeg[32001] = {};

void solve() {
    priority_queue<int, vector<int>, greater<int>> pq;
    for(int i=1; i<=N; i++) {
        if(!indeg[i]) pq.push(i);
    }
    vector<int> answer;
    while(!pq.empty()) {
        int cur = pq.top();
        pq.pop();
        answer.push_back(cur);
        for(const auto& next: node[cur]) {
            indeg[next]--;
            if(indeg[next] == 0) {
                pq.push(next);
            }
        }
    }
    for(const auto& el: answer) {
        cout << el << ' ';
    }
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cin >> N >> M;
    for(int i=0; i<M; i++){
        int A, B;
        cin >> A >> B;
        node[A].push_back(B);
        indeg[B]++;
    }
    solve();
}