oj.uz

Submission #938390

# Submission time Handle Problem Language Result Execution time Memory
938390 2024-03-05T05:39:40 Z vjudge1 One-Way Streets (CEOI17_oneway) C++17
60 / 100
 3000 ms 21820 KB 
#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define all(a) a.begin(), a.end()
const int N = 2e5;
const int mod = 1e9 + 7;

/*
5 5
1 2
1 2
4 3
2 3
4 5
2
4 5
1 3
*/

signed main(){
	int n, m; cin >> n >> m;
	vector<int> g[n+1];
	vector<pair<int, int> > edge;
	for(int i = 1;i <= m; i++){
		int a, b; cin >> a >> b;
		edge.push_back({a, b});
		g[a].push_back(b);
		g[b].push_back(a);
	}
	int q; cin >> q;
	vector<pair<int, int> > Q(q);
	for(int i = 0;i < q; i++){
		cin >> Q[i].ff >> Q[i].ss;
	}
	vector<int> in(n+1, -1), out(n+1, -1);
	vector<char> ans(m, '#');
	vector<int> par(n+1);
	vector<int> used(n+1, 0);
	int timer = 1;
	map<pair<int, int>, int> mp;
	//cout << "bridges : " << '\n';
	function<void(int, int)> bridges=[&](int v, int p){
		in[v] = timer;
		out[v] = timer++;
		par[v] = p;
		used[v] = 1;
		int flag = 0;
		for(int to : g[v]){
			
			if(!used[to]){
				bridges(to, v);
				out[v] = min(out[v], out[to]);
			}else{
				if(to == p){
					if(flag){
						out[v] = min(out[v], in[to]);
					}
					flag = 1;
				}else
				out[v] = min(out[v], in[to]);
			}
		}
		if(p != -1 && in[v] == out[v]){
			//cout << v << ' ' << p << '\n';
			mp[make_pair(min(v, p), max(v, p))] = 1;
		}
	};
	//cout << '\n';
	for(int i = 1;i <= n; i++){
		if(!used[i]){
			bridges(i, -1);
		}
	}
	for(int i = 0;i < m; i++){
		auto [a, b] = edge[i];
		if(a > b) swap(a, b);
		if(!mp.count({a, b})){
			ans[i] = 'B';
		}
	}
	vector<int> path, check;
	
	function<void(int, int)> dfs=[&](int v, int finish){
		check.push_back(v);
		used[v] = 1;
		if(v == finish){
			path = check;
			return;
		}
		for(int to : g[v]){
			if(used[to]) continue;
			dfs(to, finish);
		}
		check.pop_back();
	};
	set<pair<int, int> > st;
	for(auto [a, b] : Q){
		path.clear();
		check.clear();
		for(int i = 1;i <= n; i++) used[i] = 0;
		dfs(a, b);
		for(int i = 0;i + 1 < (int)path.size(); i++){
			st.insert(make_pair(path[i], path[i+1]));
		}	
	}
	for(int i = 0;i < m; i++){
		if(ans[i] != '#') continue;
		if(st.count(edge[i])){
			ans[i] = 'R';
		}else if(st.count({edge[i].ss, edge[i].ff})){
			ans[i] = 'L';
		}
	}
	for(int i = 0;i < m; i++){
		if(ans[i] == '#') ans[i] = 'B';
		cout << ans[i];
	}
	
	
	return 0;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 460 KB Output is correct
6 Correct 2 ms 512 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 2 ms 600 KB Output is correct
9 Correct 2 ms 348 KB Output is correct
10 Correct 2 ms 348 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 460 KB Output is correct
6 Correct 2 ms 512 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 2 ms 600 KB Output is correct
9 Correct 2 ms 348 KB Output is correct
10 Correct 2 ms 348 KB Output is correct
11 Correct 331 ms 8112 KB Output is correct
12 Correct 468 ms 10592 KB Output is correct
13 Correct 720 ms 14320 KB Output is correct
14 Correct 789 ms 17176 KB Output is correct
15 Correct 782 ms 17296 KB Output is correct
16 Correct 128 ms 14792 KB Output is correct
17 Correct 719 ms 20072 KB Output is correct
18 Correct 444 ms 14792 KB Output is correct
19 Correct 689 ms 20892 KB Output is correct
20 Correct 498 ms 11336 KB Output is correct
21 Correct 344 ms 7748 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 3 ms 460 KB Output is correct
6 Correct 2 ms 512 KB Output is correct
7 Correct 3 ms 604 KB Output is correct
8 Correct 2 ms 600 KB Output is correct
9 Correct 2 ms 348 KB Output is correct
10 Correct 2 ms 348 KB Output is correct
11 Correct 331 ms 8112 KB Output is correct
12 Correct 468 ms 10592 KB Output is correct
13 Correct 720 ms 14320 KB Output is correct
14 Correct 789 ms 17176 KB Output is correct
15 Correct 782 ms 17296 KB Output is correct
16 Correct 128 ms 14792 KB Output is correct
17 Correct 719 ms 20072 KB Output is correct
18 Correct 444 ms 14792 KB Output is correct
19 Correct 689 ms 20892 KB Output is correct
20 Correct 498 ms 11336 KB Output is correct
21 Correct 344 ms 7748 KB Output is correct
22 Execution timed out 3020 ms 21820 KB Time limit exceeded
23 Halted 0 ms 0 KB -