oj.uz

Submission #1106908

# Submission time Handle Problem Language Result Execution time Memory
1106908 2024-10-31T09:06:12 Z asli_bg One-Way Streets (CEOI17_oneway) C++11
100 / 100
 379 ms 53664 KB 
#pragma GCC optimize("O3,unroll-loops")
 
#include<bits/stdc++.h>
using namespace std;
 
#define int long long
 
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define FOR(i,a) for(int i=0;i<(a);i++)
#define FORE(i,a,b) for(int i=(a);i<(b);i++)
 
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<pii> vii;
 
#define cont(x) for(auto el:x) {cout<<el<<' ';} cout<<endl;
#define endl '\n'
#define contp(x) for(auto el:x) {cout<<el.fi<<'-'<<el.se<<' ';} cout<<endl;
#define pb push_back
 
#define sp <<' '<<
 
#define DEBUG(x) {cout<<(#x) sp x<<endl;}
#define carp(x,y) ((x%MOD)*(y%MOD))%MOD
#define topla(x,y) ((x%MOD)+(y%MOD))%MOD
 
const int MAXN=1e5+5;
 
int n,m;
vi adj[MAXN];
int tane[MAXN], dep[MAXN], low[MAXN], comp[MAXN];
bool vis[MAXN], isbridge[MAXN];
 
map<pii,int> ind;

int say;

vii g[MAXN];
vector<char> ans;
 
set<pii> tut;
set<pii> temp;
vii edge;
 
void dfs(int nd,int ata,int h){
    dep[nd]=h;
    low[nd]=h;
    for(auto kom:adj[nd]){
        if(kom==ata) continue;
        if(vis[kom]){
            if(dep[kom]<=dep[nd]){ //back edge
                low[nd]=min(low[nd],dep[kom]);
            }
            continue;
        }
        vis[kom]=true;
        dfs(kom,nd,h+1);
        low[nd]=min(low[nd],low[kom]);
    }
 
    if(ata!=0 and low[nd]>=dep[nd] and tane[ind[{ata,nd}]]<=1){
        isbridge[ind[{ata,nd}]]=true;
        edge.pb({ata,nd});
    }
}
 
void dfs2(int nd,int ata){ //componentlere ayir
    comp[nd]=say;
    for(auto kom:adj[nd]){
        if(kom==ata) continue;
        if(vis[kom]) continue;
        if(isbridge[ind[{nd,kom}]]) continue;
        vis[kom]=true;
        dfs2(kom,nd);
    }
}


int top[MAXN];
void dfs3(int nd,int ata,int ind){
    for(auto el:g[nd]){
        int kom=el.fi;
        int yer=el.se;
        if(kom==ata) continue;
        if(vis[kom]) continue;
        vis[kom]=true;
        dfs3(kom,nd,yer);
        top[nd]+=top[kom];
    }
 
    if(ind==-1) return;
 
    if(top[nd]<0){ //bana edge çek
        if(tut.count({ata,nd})) ans[ind]='R';
        else ans[ind]='L';
    }
    else if(top[nd]>0){ //benden edge çek
        if(tut.count({ata,nd})) ans[ind]='L';
        else ans[ind]='R';
    }
}
 
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    
    cin>>n>>m;
 
    say=1;
    FOR(i,m){
        int a,b;
        cin>>a>>b;
 
        adj[a].pb(b);
        adj[b].pb(a);
 
        //yeni bir edgese
        if(ind[{a,b}]==0) ind[{a,b}]=ind[{b,a}]=say++;
        else say++;
        tane[ind[{a,b}]]++;
        temp.insert({a,b});
    }
    
    //bridgeleri bul
    FORE(i,1,n+1){
        if(!vis[i]){
            vis[i]=true;
            dfs(i,0,0);
        }
    } 
 
    memset(vis,0,sizeof vis);

    //componentlere ayir
    say=1;
    FORE(i,1,n+1){
        if(!vis[i]){
            vis[i]=true;
            dfs2(i,0);
            say++;
        }
    }  
 
    for(auto el:temp){
        if(comp[el.fi]==comp[el.se]) continue;
        tut.insert({comp[el.fi],comp[el.se]});
    }
 
    //create the condensation graph
    for(auto el:edge){
        g[comp[el.fi]].pb({comp[el.se],ind[el]});
        g[comp[el.se]].pb({comp[el.fi],ind[el]});
    }
 
    int p;
    cin>>p;
    while(p--){
        int a,b;
        cin>>a>>b;
        top[comp[a]]++;
        top[comp[b]]--;
    }
 
    ans.resize(m+1,'B');
 
    memset(vis,0,sizeof vis);
    
    //yönleri belirle
    FORE(i,1,say+1){
        if(!vis[i]){
            vis[i]=true;
            dfs3(i,0,-1);
        }
    }
 
    FORE(i,1,m+1) cout<<ans[i];
    cout<<endl;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 9040 KB Output is correct
2 Correct 2 ms 9040 KB Output is correct
3 Correct 4 ms 9464 KB Output is correct
4 Correct 4 ms 9296 KB Output is correct
5 Correct 4 ms 9296 KB Output is correct
6 Correct 3 ms 9296 KB Output is correct
7 Correct 4 ms 9468 KB Output is correct
8 Correct 4 ms 9296 KB Output is correct
9 Correct 3 ms 9464 KB Output is correct
10 Correct 3 ms 9296 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 9040 KB Output is correct
2 Correct 2 ms 9040 KB Output is correct
3 Correct 4 ms 9464 KB Output is correct
4 Correct 4 ms 9296 KB Output is correct
5 Correct 4 ms 9296 KB Output is correct
6 Correct 3 ms 9296 KB Output is correct
7 Correct 4 ms 9468 KB Output is correct
8 Correct 4 ms 9296 KB Output is correct
9 Correct 3 ms 9464 KB Output is correct
10 Correct 3 ms 9296 KB Output is correct
11 Correct 210 ms 32988 KB Output is correct
12 Correct 208 ms 34120 KB Output is correct
13 Correct 214 ms 35912 KB Output is correct
14 Correct 271 ms 38140 KB Output is correct
15 Correct 268 ms 39104 KB Output is correct
16 Correct 323 ms 45368 KB Output is correct
17 Correct 335 ms 48140 KB Output is correct
18 Correct 324 ms 45240 KB Output is correct
19 Correct 335 ms 50112 KB Output is correct
20 Correct 185 ms 33140 KB Output is correct
21 Correct 174 ms 31944 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 9040 KB Output is correct
2 Correct 2 ms 9040 KB Output is correct
3 Correct 4 ms 9464 KB Output is correct
4 Correct 4 ms 9296 KB Output is correct
5 Correct 4 ms 9296 KB Output is correct
6 Correct 3 ms 9296 KB Output is correct
7 Correct 4 ms 9468 KB Output is correct
8 Correct 4 ms 9296 KB Output is correct
9 Correct 3 ms 9464 KB Output is correct
10 Correct 3 ms 9296 KB Output is correct
11 Correct 210 ms 32988 KB Output is correct
12 Correct 208 ms 34120 KB Output is correct
13 Correct 214 ms 35912 KB Output is correct
14 Correct 271 ms 38140 KB Output is correct
15 Correct 268 ms 39104 KB Output is correct
16 Correct 323 ms 45368 KB Output is correct
17 Correct 335 ms 48140 KB Output is correct
18 Correct 324 ms 45240 KB Output is correct
19 Correct 335 ms 50112 KB Output is correct
20 Correct 185 ms 33140 KB Output is correct
21 Correct 174 ms 31944 KB Output is correct
22 Correct 379 ms 48044 KB Output is correct
23 Correct 374 ms 45300 KB Output is correct
24 Correct 373 ms 45420 KB Output is correct
25 Correct 348 ms 53664 KB Output is correct
26 Correct 375 ms 47300 KB Output is correct
27 Correct 355 ms 45524 KB Output is correct
28 Correct 59 ms 12620 KB Output is correct
29 Correct 197 ms 32252 KB Output is correct
30 Correct 201 ms 32508 KB Output is correct
31 Correct 207 ms 33096 KB Output is correct
32 Correct 199 ms 36288 KB Output is correct