oj.uz

Submission #631166

# Submission time Handle Problem Language Result Execution time Memory
631166 2022-08-17T18:16:15 Z NintsiChkhaidze One-Way Streets (CEOI17_oneway) C++14
0 / 100
 3 ms 2772 KB 
#include <bits/stdc++.h>
#define s second
#define f first
#define pb push_back
using namespace std;

const int N = 100005;
vector <pair<int,int> > v[N];
int tin[N],low[N],a[N],b[N],open[N],close[N];
bool bridge[N],vis[N],F[N];
int f[N],o,c,cnt;

void dfs(int x,int par){
    f[x] = 1;
    tin[x] = low[x] = cnt++;
    for (auto [to,id]: v[x]){
        if (to == par) continue;
        if (f[to]){
            low[x] = min(low[x], tin[to]);
        }else{
            dfs(to,x);
            low[x] = min(low[x], low[to]);
            if (low[to] > tin[x])
                bridge[id] = 1;
        }
    }
}

void DFS(int x){
    vis[x] = 1;
    if (open[x]) {
        o++;
        f[open[x]]++;
        if (f[open[x]] == 0) o--,c--;
    }

    if (close[x]) {
        f[close[x]]--;
        c++;
        if (f[close[x]] == 0) c--,o--;
    }
    for (auto [to,id]: v[x])
        if (!vis[to] && !F[to]) DFS(to);
    
}
int main (){
    ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
    int n,m;
    cin>>n>>m;

    for (int i = 1; i <= m; i++){
        cin>>a[i]>>b[i];
        v[a[i]].pb({b[i],i});
        v[b[i]].pb({a[i],i});
    }
    for (int i= 1; i <= n; i++)
        if (!f[i]) dfs(i,i); 

    int k;
    cin>>k;
    for (int i = 1; i <= k; i++){
        int x,y;
        cin>>x>>y;
        open[x] = i;
        close[y] = i;
    }

    for (int i = 1; i <= m; i++){
        if (bridge[i] == 0) cout<<'B';
        else{
            o = 0,c=0;
            for (int j=1;j<=n;j++) f[j] = 0,vis[j] = 0;
            F[b[i]] = 1;DFS(a[i]);
            F[b[i]] = 0;
            
            if(o && !c) cout<<'R';
            else if (!o && c) cout<<'L';
            else cout<<'B';
        }
    }
}

Compilation message

oneway.cpp: In function 'void dfs(int, int)':
oneway.cpp:16:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   16 |     for (auto [to,id]: v[x]){
      |               ^
oneway.cpp: In function 'void DFS(int)':
oneway.cpp:42:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   42 |     for (auto [to,id]: v[x])
      |               ^

Subtask #1
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2680 KB Output is correct
3 Incorrect 3 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2680 KB Output is correct
3 Incorrect 3 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2644 KB Output is correct
2 Correct 1 ms 2680 KB Output is correct
3 Incorrect 3 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -