Submission #704857

#	Time	Username	Problem	Language	Result	Execution time	Memory
704857		PixelCat	Naboj (COCI22_naboj)	C++14	110 / 110	252 ms	23928 KiB

naboj

#include <bits/stdc++.h>
#define For(i, a, b) for(int i = a; i <= b; i++)
#define Forr(i, a, b) for(int i = a; i >= b; i--)
#define F first
#define S second
#define sz(x) ((int)x.size())
#define all(x) x.begin(), x.end()
#define eb emplace_back
#define int LL
using namespace std;
using LL = long long;
using pii = pair<int, int>;

const int MAXN = 200020;

vector<int> adj[MAXN];
int deg[MAXN];

int32_t main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    // nya ><
    int n, m; cin >> n >> m;
    For(i, 1, m) {
        int a, b; cin >> a >> b;
        adj[a].eb(b);
        deg[b]++;
    }
    queue<int> que;
    vector<int> ans;
    For(i, 1, n) if(deg[i] == 0) {
        que.emplace(i);
    }
    while(!que.empty()) {
        int now = que.front(); que.pop();
        ans.eb(now);
        for(auto &i:adj[now]) {
            deg[i]--;
            if(!deg[i]) que.emplace(i);
        }
    }
    if(sz(ans) != n) {
        cout << "-1\n";
    } else {
        cout << n << "\n";
        reverse(all(ans));
        for(auto &i:ans) cout << i << " 1\n";
    }
    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 25 / 25
• Subtask 3: 70 / 70