oj.uz

Submission #115058

# Submission time Handle Problem Language Result Execution time Memory
115058 2019-06-05T03:37:32 Z minhtung0404 One-Way Streets (CEOI17_oneway) C++17
30 / 100
 3000 ms 18200 KB 
//https://csacademy.com/contest/ceoi-2017-day-1/task/one-way-streets/statement/

#include<bits/stdc++.h>
const int N = 1e5 + 5;
using namespace std;

struct edge{
    int u, v, id;

    edge(int u, int v, int id) : u(u), v(v), id(id) {}
    edge() {}
};

vector <edge> mv;
typedef pair <int, int> ii;
vector <ii> G[N], G2[N];

int n, m, q, pset[N];
int num[N], low[N], cnt, d[N], ans[N];
bool visited[N];
ii p[N];

int Find(int i) {return ((pset[i] == i) ? i : pset[i] = Find(pset[i]));}

void dsu(int u, int v){
    u = Find(u); v = Find(v);
    if (u == v) return;
    pset[v] = u;
}

void dfs(int u, int id){
    num[u] = low[u] = ++cnt;
    for (auto p : G[u]){
        int v = p.first;
        if (id == abs(p.second)) continue;
        if (num[v]) {
            low[u] = min(low[u], num[v]);
            dsu(u, v);
        }
        else {
            dfs(v, abs(p.second));
            low[u] = min(low[u], low[v]);
            if (low[v] <= num[u]) dsu(u, v);
            else{
                mv.push_back(edge(u, v, p.second));
            }
        }
    }
}

void redfs(int u){
    for(auto x : G2[u]){
        if (x == p[u]) continue;
        int v = x.first;
        p[v].first = u; p[v].second = -x.second;
        d[v] = d[u] + 1;
        redfs(v);
    }
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    cin >> n >> m;
    for (int i = 1; i <= n; i++) pset[i] = i;
    for (int i = 1; i <= m; i++){
        int u, v;
        cin >> u >> v;
        G[u].push_back(ii(v, i));
        G[v].push_back(ii(u, -i));
    }
    for (int i = 1; i <= n; i++) if (!num[i]) dfs(i, 0);
    for (auto ed : mv){
        ed.u = Find(ed.u); ed.v = Find(ed.v);
        G2[ed.u].push_back(ii(ed.v, ed.id));
        G2[ed.v].push_back(ii(ed.u, -ed.id));
    }
    for (int i = 1; i <= n; i++) if (pset[i] == i && !visited[i]) redfs(i);
    cin >> q;
    cnt = 0;
    while (q--){
        int u, v;
        cin >> u >> v;
        u = Find(u); v = Find(v);
        while (u != v){
            if (d[u] > d[v]) {
                dsu(p[u].first, u);
                ans[abs(p[u].second)] = ((p[u].second > 0) ? 1 : 2);
                u = Find(p[u].first);
                cnt++;
            }
            else{
                dsu(p[v].first, v);
                ans[abs(p[v].second)] = ((p[v].second > 0) ? 2 : 1);
                v = Find(p[v].first);
                cnt++;
            }
        if (cnt > n) assert(0);
        }
    }
    for (int i = 1; i <= m; i++){
        if (ans[i] == 0) cout << "B";
        if (ans[i] == 1) cout << "R";
        if (ans[i] == 2) cout << "L";
    }
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 8 ms 5248 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 8 ms 5248 KB Output is correct
8 Correct 7 ms 5248 KB Output is correct
9 Correct 6 ms 5120 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 8 ms 5248 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 8 ms 5248 KB Output is correct
8 Correct 7 ms 5248 KB Output is correct
9 Correct 6 ms 5120 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 51 ms 9848 KB Output is correct
12 Correct 62 ms 11256 KB Output is correct
13 Correct 91 ms 13000 KB Output is correct
14 Correct 85 ms 14964 KB Output is correct
15 Correct 99 ms 15348 KB Output is correct
16 Correct 204 ms 16388 KB Output is correct
17 Execution timed out 3046 ms 18200 KB Time limit exceeded
18 Halted 0 ms 0 KB -

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4992 KB Output is correct
2 Correct 6 ms 4992 KB Output is correct
3 Correct 6 ms 5120 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 8 ms 5248 KB Output is correct
6 Correct 6 ms 5120 KB Output is correct
7 Correct 8 ms 5248 KB Output is correct
8 Correct 7 ms 5248 KB Output is correct
9 Correct 6 ms 5120 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 51 ms 9848 KB Output is correct
12 Correct 62 ms 11256 KB Output is correct
13 Correct 91 ms 13000 KB Output is correct
14 Correct 85 ms 14964 KB Output is correct
15 Correct 99 ms 15348 KB Output is correct
16 Correct 204 ms 16388 KB Output is correct
17 Execution timed out 3046 ms 18200 KB Time limit exceeded
18 Halted 0 ms 0 KB -