oj.uz

답안 #468085

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
468085 2021-08-26T14:13:18 Z Vladth11 One-Way Streets (CEOI17_oneway) C++14
0 / 100
 2 ms 2636 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define debug(x) cerr << #x << " " << x << "\n"
#define debugs(x) cerr << #x << " " << x << " "
#pragma GCC optimize("Ofast,unroll-loops")

using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef pair <ll, ll> pii;
typedef pair <long double, pii> muchie;
typedef tree <ll, null_type, less_equal <ll>, rb_tree_tag, tree_order_statistics_node_update> OST;

const ll NMAX = 100001;
const ll INF = (1LL << 60);
const ll HALF = (1LL << 59);
const ll MOD = 30013;
const ll BLOCK = 318;
const ll base = 31;
const ll nr_of_bits = 21;

int n, m;
int lvl[NMAX];
int dp[NMAX];
int viz[NMAX];
int cnt;
int dest[NMAX];
int sursa[NMAX];
int surse[NMAX];
int deste[NMAX];
int comp[NMAX];
int parent[NMAX];
vector <int> v[NMAX];

void DFS(int node, int p){
    lvl[node] = lvl[p] + 1;
    parent[node] = p;
    for(auto x : v[node]){
        if(!lvl[x]){
            DFS(x, node);
            dp[node] += dp[x];
        }else if(lvl[x] > lvl[node]){
            dp[node]--;
        }else{
            dp[node]++;
        }
    }
    if(node != 1) ///sau root
        dp[node]--;
}

void assignComp(int node, int p){
    if(!dp[node])
        cnt++;
    comp[node] = cnt;
    for(auto x : v[node]){
        if(!comp[x]){
            assignComp(x, node);
        }
    }
}

pii special[NMAX];
pii edges[NMAX];

void calc(int node, int p){
    viz[node] = 1;
    surse[comp[node]] += sursa[node];
    deste[comp[node]] += dest[node];
    for(auto x : v[node]){
        if(!viz[x]){
            calc(x, node);
            if(comp[node] != comp[x]){
                surse[comp[node]] += surse[comp[x]];
                deste[comp[node]] += deste[comp[x]];
            }
        }
    }
}

int main() {
    int i;
    /// Poate sunt mai multe componente
    cin >> n >> m;
    for(i = 1; i <= m; i++){
        int x, y;
        cin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
        edges[i] = {x, y};
    }

    DFS(1, 0);
    assignComp(1, 0);
    int q;
    cin >> q;
    for(i = 1; i <= q; i++){
        int x, y;
        cin >> x >> y;
        special[i] = {x, y};
        if(comp[x] == comp[y])
            continue;
        sursa[x] = 1;
        dest[y] = 1;
    }
    calc(1, 0);
    for(i = 1; i <= m; i++){
        int x = edges[i].first;
        int y = edges[i].second;
        if(lvl[x] > lvl[y]){
            swap(x, y);
        }
        if(parent[y] != x){
            cout << "B";
            continue;
        }
        if(dp[y] != 0){
            cout << "B";
            continue;
        }
        if(!deste[comp[y]] && !surse[comp[y]]){
            cout << "B";
            continue;
        }
        if(surse[comp[y]] > 0){
            if(y == edges[i].first){
                cout << "R";
            }else{
                cout << "L";
            }
            continue;
        }
        if(y == edges[i].first){
            cout << "L";
        }else{
            cout << "R";
        }
    }
    return 0;
}

Subtask #1
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 2 ms 2636 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 2 ms 2636 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 2 ms 2636 KB Output isn't correct
2 Halted 0 ms 0 KB -