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Submission #873725

# Submission time Handle Problem Language Result Execution time Memory
873725 2023-11-15T14:34:55 Z mdobric One-Way Streets (CEOI17_oneway) C++14
60 / 100
 3000 ms 34864 KB 
#include <bits/stdc++.h>
using namespace std;

int n, m, p;
int a[100005], b[100005], poc[100005], kraj[100005];
vector <pair <int, int> > v[100005];
vector <pair <int, int> > e[100005];
int dt[100005], ft[100005], lw[100005];
int most[100005], blok[100005];
int brojac = 1;
int br1 = 1, br2 = 1;
int parent[100005];
int rez[100005];
map <int, bool> mp[100005];
map <int, bool> :: iterator it;

int find (int x){
	if (parent[x] == x){
		return x;
	}
	return parent[x] = find(parent[x]);
}

void unite (int x, int y){
	int px = find(parent[x]);
	int py = find(parent[y]);
	if (px == py){
		return;
	}
	if (mp[x].size() > mp[y].size()){
		swap(px, py);
	}
	
	for (auto i : mp[px]){
		if (mp[py][i.first] == 1){
			mp[py].erase(i.first);
		}
		else{
			mp[py][i.first] = 1;
		}	
	}
	mp[px].clear();
	
	/*
	while (mp[px].size() > 0){
		//mp[px].begin();
		it = mp[px].begin();
		mp[py][it -> first]++;
		if (mp[py][it -> first] == 2){
			mp[py].erase(it -> first);
		}
		mp[px].erase(mp[px].begin());
	}
	*/
	parent[px] = py;
	return;
}

void dfs (int x, int p, int cesta){
	//cout << " aaa " << x << " " << p << endl;
	blok[x] = brojac;
	lw[x] = dt[x];
	for (int i = 0; i < v[x].size(); i++){
		int x_novi = v[x][i].first;
		int in = v[x][i].second;
		if (dt[x_novi] == 0 and cesta != in and x != x_novi){
			e[x].push_back(make_pair(x_novi, in));
			dt[x_novi] = br1;
			parent[x_novi] = x_novi;
			br1++;
			dfs(x_novi, x, in);
			lw[x] = min(lw[x], lw[x_novi]);
		}
		else
		if (cesta != in and x != x_novi){
			lw[x] = min(lw[x], dt[x_novi]);
		}
	}
	if (cesta != -1 and lw[x] == dt[x]){
		most[cesta] = 1;
	}
	ft[x] = br2;
	br2++;
	return;
}

void dfs2 (int x, int cesta){
	for (int i = 0; i < e[x].size(); i++){
		int x_novi = e[x][i].first;
		int in = e[x][i].second;
		dfs2(x_novi, in);
		unite(x, x_novi);
	}
	int px = find(x);
	if (cesta != -1 and mp[px].size() > 0){
		for (auto i : mp[px]){
			rez[cesta] = i.first;
			break;
		}
	}
	return;
}

int main (void){
	
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	cin >> n >> m;
	for (int i = 1; i <= m; i++){
		cin >> a[i] >> b[i];
		v[a[i]].push_back(make_pair(b[i], i));
		v[b[i]].push_back(make_pair(a[i], i));
	}
	for (int i = 1; i <= n; i++){
		if (blok[i] == 0){
			blok[i] = brojac;
			br1 = 1, br2 = 1;
			dt[i] = 1;
			br1++;
			parent[i] = i;
			dfs(i, 0, -1);
			brojac++;
		}
	}
	/*
	for (int i = 1; i <= n; i++){
		cout << blok[i] << endl;
		cout << i << " : ";
		for (int j = 0; j < e[i].size(); j++){
			cout << e[i][j].first << " ";
		}
		cout << endl;
	}
	*/
	cin >> p;
	for (int i = 1; i <= p; i++){
		cin >> poc[i] >> kraj[i];
		if (poc[i] != kraj[i]){
			mp[poc[i]][i] = 1;
			mp[kraj[i]][i] = 1;
		}
		
	}
	brojac = 1;
	for (int i = 1; i <= n; i++){
		if (blok[i] == brojac){
			dfs2(i, -1);
			brojac++;
		}
	}
	//cout << "aaa" << endl;
	//dfs2(1, -1);
	for (int i = 1; i <= m; i++){
		if (rez[i] == 0 or most[i] == 0){
			cout << "B";
		}
		else{
			int k = kraj[rez[i]];
			int p = poc[rez[i]];
			//cout << a[i] << " " << b[i] << " " << p << " " << k << endl;
			if ((dt[a[i]] < dt[b[i]] and dt[b[i]] <= dt[k] and ft[b[i]] >= ft[k]) or (dt[a[i]] > dt[b[i]] and dt[a[i]] <= dt[p] and ft[a[i]] >= ft[p])){
				cout << "R";
			}
			else{
				cout << "L";
			}
		}
	}
	
	return 0;
}

Compilation message

oneway.cpp: In function 'void dfs(int, int, int)':
oneway.cpp:63:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |  for (int i = 0; i < v[x].size(); i++){
      |                  ~~^~~~~~~~~~~~~
oneway.cpp: In function 'void dfs2(int, int)':
oneway.cpp:88:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |  for (int i = 0; i < e[x].size(); i++){
      |                  ~~^~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 2 ms 12888 KB Output is correct
3 Correct 3 ms 12892 KB Output is correct
4 Correct 3 ms 12908 KB Output is correct
5 Correct 4 ms 12888 KB Output is correct
6 Correct 4 ms 12892 KB Output is correct
7 Correct 5 ms 13144 KB Output is correct
8 Correct 3 ms 12888 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 3 ms 12892 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 2 ms 12888 KB Output is correct
3 Correct 3 ms 12892 KB Output is correct
4 Correct 3 ms 12908 KB Output is correct
5 Correct 4 ms 12888 KB Output is correct
6 Correct 4 ms 12892 KB Output is correct
7 Correct 5 ms 13144 KB Output is correct
8 Correct 3 ms 12888 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 3 ms 12892 KB Output is correct
11 Correct 33 ms 19536 KB Output is correct
12 Correct 41 ms 20816 KB Output is correct
13 Correct 62 ms 22100 KB Output is correct
14 Correct 76 ms 23120 KB Output is correct
15 Correct 61 ms 23000 KB Output is correct
16 Correct 44 ms 20564 KB Output is correct
17 Correct 82 ms 23044 KB Output is correct
18 Correct 45 ms 20560 KB Output is correct
19 Correct 83 ms 24656 KB Output is correct
20 Correct 50 ms 20564 KB Output is correct
21 Correct 43 ms 20300 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 2 ms 12888 KB Output is correct
3 Correct 3 ms 12892 KB Output is correct
4 Correct 3 ms 12908 KB Output is correct
5 Correct 4 ms 12888 KB Output is correct
6 Correct 4 ms 12892 KB Output is correct
7 Correct 5 ms 13144 KB Output is correct
8 Correct 3 ms 12888 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 3 ms 12892 KB Output is correct
11 Correct 33 ms 19536 KB Output is correct
12 Correct 41 ms 20816 KB Output is correct
13 Correct 62 ms 22100 KB Output is correct
14 Correct 76 ms 23120 KB Output is correct
15 Correct 61 ms 23000 KB Output is correct
16 Correct 44 ms 20564 KB Output is correct
17 Correct 82 ms 23044 KB Output is correct
18 Correct 45 ms 20560 KB Output is correct
19 Correct 83 ms 24656 KB Output is correct
20 Correct 50 ms 20564 KB Output is correct
21 Correct 43 ms 20300 KB Output is correct
22 Execution timed out 3017 ms 34864 KB Time limit exceeded
23 Halted 0 ms 0 KB -