oj.uz

Submission #699193

# Submission time Handle Problem Language Result Execution time Memory
699193 2023-02-16T04:57:38 Z beepbeepsheep Naboj (COCI22_naboj) C++17
110 / 110
 869 ms 85216 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

typedef tree<long long, null_type, less_equal<>,
        rb_tree_tag, tree_order_statistics_node_update>
        ordered_set;
#define ll long long
#define ii pair<ll,ll>
#define endl '\n'
#define cerr if (0) cerr
const ll inf=1e15;
const ll maxn=2e5+5;
const ll mod=1e9+7;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

ll cnt[maxn][2];
bool vis[maxn];
set<ii> adj[maxn];
queue<ii> q;
int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	ll n,m,a,b;
	cin>>n>>m;
	for (int i=0;i<m;i++){
		cin>>a>>b;
		adj[a].emplace(b,0);
		adj[b].emplace(a,1);
		cnt[a][0]++;
		cnt[b][1]++;
	}
	for (int i=1;i<=n;i++){
		cerr<<cnt[i][0]<<' '<<cnt[i][1]<<endl;
		if (cnt[i][0]==0){
			q.emplace(i,0);
			vis[i]=1;
		} else if (cnt[i][1]==0){
			q.emplace(i,1);
			vis[i]=1;
		}
	}
	stack<ii> s;
	while (q.size()){
		tie(a,b)=q.front();
		cerr<<a<<' '<<b<<'x'<<endl;
		q.pop();
		for (auto [x,y]:adj[a]){
			cerr<<a<<' '<<x<<' '<<y<<endl;
			adj[x].erase(make_pair(a,b));
			if (cnt[x][b]==1 && vis[x]==0){
				q.emplace(x,b);
				vis[x]=1;
			}
			cnt[x][b]--;
		}
		s.emplace(a,b);
	}
	for (int i=1;i<=n;i++){
		cerr<<cnt[i][0]<<' '<<cnt[i][1]<<'y'<<endl;
		if (cnt[i][0] && cnt[i][1]){
			cout<<-1;
			return 0;
		}
	}
	cout<<s.size()<<endl;
	while (s.size()){
		cout<<s.top().first<<' '<<s.top().second<<endl;
		s.pop();
	}
	return 0;
}

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 5 ms 9684 KB Output is correct
3 Correct 5 ms 9684 KB Output is correct
4 Correct 5 ms 9684 KB Output is correct
5 Correct 5 ms 9684 KB Output is correct
6 Correct 5 ms 9684 KB Output is correct
7 Correct 5 ms 9656 KB Output is correct
8 Correct 5 ms 9684 KB Output is correct
9 Correct 5 ms 9684 KB Output is correct
10 Correct 5 ms 9724 KB Output is correct
11 Correct 5 ms 9684 KB Output is correct
12 Correct 5 ms 9648 KB Output is correct
13 Correct 5 ms 9728 KB Output is correct
14 Correct 5 ms 9684 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 278 ms 43124 KB Output is correct
2 Correct 280 ms 45632 KB Output is correct
3 Correct 159 ms 28476 KB Output is correct
4 Correct 310 ms 45580 KB Output is correct
5 Correct 293 ms 45768 KB Output is correct
6 Correct 289 ms 45576 KB Output is correct
7 Correct 298 ms 45712 KB Output is correct
8 Correct 211 ms 37700 KB Output is correct
9 Correct 286 ms 45544 KB Output is correct
10 Correct 319 ms 45652 KB Output is correct

Subtask #3
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 5 ms 9684 KB Output is correct
3 Correct 5 ms 9684 KB Output is correct
4 Correct 5 ms 9684 KB Output is correct
5 Correct 5 ms 9684 KB Output is correct
6 Correct 5 ms 9684 KB Output is correct
7 Correct 5 ms 9656 KB Output is correct
8 Correct 5 ms 9684 KB Output is correct
9 Correct 5 ms 9684 KB Output is correct
10 Correct 5 ms 9724 KB Output is correct
11 Correct 5 ms 9684 KB Output is correct
12 Correct 5 ms 9648 KB Output is correct
13 Correct 5 ms 9728 KB Output is correct
14 Correct 5 ms 9684 KB Output is correct
15 Correct 278 ms 43124 KB Output is correct
16 Correct 280 ms 45632 KB Output is correct
17 Correct 159 ms 28476 KB Output is correct
18 Correct 310 ms 45580 KB Output is correct
19 Correct 293 ms 45768 KB Output is correct
20 Correct 289 ms 45576 KB Output is correct
21 Correct 298 ms 45712 KB Output is correct
22 Correct 211 ms 37700 KB Output is correct
23 Correct 286 ms 45544 KB Output is correct
24 Correct 319 ms 45652 KB Output is correct
25 Correct 489 ms 68072 KB Output is correct
26 Correct 399 ms 56584 KB Output is correct
27 Correct 500 ms 65580 KB Output is correct
28 Correct 618 ms 78772 KB Output is correct
29 Correct 337 ms 50124 KB Output is correct
30 Correct 580 ms 77540 KB Output is correct
31 Correct 77 ms 21408 KB Output is correct
32 Correct 336 ms 49220 KB Output is correct
33 Correct 772 ms 79920 KB Output is correct
34 Correct 367 ms 51784 KB Output is correct
35 Correct 775 ms 80564 KB Output is correct
36 Correct 330 ms 48112 KB Output is correct
37 Correct 691 ms 73576 KB Output is correct
38 Correct 563 ms 64536 KB Output is correct
39 Correct 768 ms 79020 KB Output is correct
40 Correct 623 ms 69860 KB Output is correct
41 Correct 644 ms 69148 KB Output is correct
42 Correct 856 ms 83720 KB Output is correct
43 Correct 421 ms 55116 KB Output is correct
44 Correct 869 ms 85216 KB Output is correct
45 Correct 367 ms 51624 KB Output is correct
46 Correct 635 ms 69912 KB Output is correct