Submission #704871

#	Time	Username	Problem	Language	Result	Execution time	Memory
704871		browntoad	Naboj (COCI22_naboj)	C++14	110 / 110	478 ms	18520 KiB

naboj

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define int ll
#define FOR(i, a, b) for (int i=(a); i<(b); i++)
#define REP(i, n) FOR(i, 0, n)
#define REP1(i, n) FOR(i, 1, n+1)
#define RREP(i, n) for (int i=(n)-1; i>=0; i--)
#define pii pair<int, int>
#define f first
#define s second
#define pb push_back
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) (int)((x).size())

const ll maxn = 2e5+5;

int n, m;
vector<int> graph[maxn];
vector<int> in(maxn);
vector<bool> occ(maxn);
void inp(){
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    cin>>n>>m;
    REP(i, m){
        int u, v; cin>>u>>v;
        graph[u].pb(v);
        in[v]++;
    }
}
vector<pii> res;
void solve(){
    queue<int> qu;
    REP1(i, n){
        if (in[i] == 0) qu.push(i);
    }
    vector<int> topo;
    while(qu.size()){
        int x=qu.front(); qu.pop();
        occ[x]=1;
        topo.pb(x);
        REP(i, SZ(graph[x])){
            in[graph[x][i]]--;
            if (in[graph[x][i]] == 0){
                qu.push(graph[x][i]);
            }
        }
    }
    bool gg=0;
    REP1(i, n){
        if (occ[i] == 0){
            gg=1;
            break;
        }
    }
    if (gg) {
        if (m==n-1) assert(0);
        cout<<-1<<endl;
        return;
    }
    assert(SZ(topo)==n);
    cout<<n<<endl;
    REP(i, n){
        cout<<topo[i]<<' '<<0<<endl;
    }


}
signed main(){
    inp();
    solve();
}

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