oj.uz

Submission #550347

# Submission time Handle Problem Language Result Execution time Memory
550347 2022-04-17T22:02:09 Z leaked One-Way Streets (CEOI17_oneway) C++17
100 / 100
 1006 ms 49088 KB 
#include <bits/stdc++.h>

#define f first
#define s second
#define m_p make_pair
#define vec vector
#define pb push_back
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define pw(x) (1LL<<(x))
#define sz(x) (int)(x).size()

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
template<class T> bool umin(T &a,const T &b){return (a>b?a=b,1:0);}
template<class T> bool umax(T &a,const T &b){return (a<b?a=b,1:0);}
const int N=5e5+1;

vec<array<int,3>> g[N];
int in[N],out[N],tt=1,fup[N],up[N][20];
char clr[N];
bool is(int a,int b){
    return in[a]<=in[b]&&out[a]>=out[b];
}
vec<array<int,3>> gr[N];
void dfs(int v,int p,int pr){
    in[v]=fup[v]=tt++;
    up[v][0]=pr;
    for(int i=1;i<20;i++) up[v][i]=up[up[v][i-1]][i-1];
    for(auto &z : g[v]){
        if(z[1]==p) continue;
        if(in[z[0]]){
            umin(fup[v],in[z[0]]);
//            if(in[z[0]]<in[v])
//                cout<<"E! "<<v<<' '<<z[0]<<endl;
            clr[z[1]]='B';
        }
        else{
//                        cout<<"E "<<v<<' '<<z[0]<<endl;

            dfs(z[0],z[1],v);
            gr[v].pb(z);
            umin(fup[v],fup[z[0]]);
//            cout<<"E "<<v<<' '<<z[0]<<' '<<in[v]<<' '<<fup[z[0]]<<endl;
            if(fup[z[0]]<=in[v])
                clr[z[1]]='B';
            else
                clr[z[1]]='.';
        }
    }
    out[v]=tt-1;
}
int dp[N][2];
string fck="LR";
void dfs2(int v){
    for(auto &z : gr[v]){
        dfs2(z[0]);
        for(int t=0;t<2;t++)
            dp[v][t]+=dp[z[0]][t];
//        cout<<dp[z[0]][0]<<' '<<
        if(dp[z[0]][0] || dp[z[0]][1]){
            if(clr[z[1]]=='B') continue;
            if(dp[z[0]][0])
                clr[z[1]]=fck[0^z[2]^1];
            else
                clr[z[1]]=fck[1^z[2]^1];
        }
        else clr[z[1]]='B';
    }
}
int lca(int a,int b){
    if(is(a,b)) return a;
    for(int i=19;i>=0;i--){
        if(!is(up[a][i],b))
            a=up[a][i];
    }
    return up[a][0];
}
signed main(){
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int n,m;
    cin>>n>>m;
    for(int i=0;i<m;i++){
        int v,u;
        cin>>v>>u;--v;--u;
        g[v].pb({u,i,0});
        g[u].pb({v,i,1});
    }
    vec<int>roots;
    for(int i=0;i<n;i++){
        if(!in[i])
            roots.pb(i),dfs(i,-1,i);
    }
    int q;
    cin>>q;
    while(q--){
        int v,u;
        cin>>v>>u;--v;--u;
        cerr<<"WO "<<v<<' '<<u<<' '<<lca(v,u)<<endl;
        dp[v][1]++;
        dp[u][0]++;
        dp[lca(v,u)][0]--;
        dp[lca(v,u)][1]--;
    }
    for(auto &z : roots)
        dfs2(z);
    for(int i=0;i<m;i++)
        cout<<clr[i];
    return 0;
}
/*
10 10 1
6 5
5 1
1 4
2 4
2 10
3 1
3 8
9 8
9 7
6 8
3 9 8

*/

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23764 KB Output is correct
2 Correct 14 ms 23820 KB Output is correct
3 Correct 13 ms 23896 KB Output is correct
4 Correct 12 ms 24016 KB Output is correct
5 Correct 13 ms 24032 KB Output is correct
6 Correct 14 ms 23952 KB Output is correct
7 Correct 17 ms 23936 KB Output is correct
8 Correct 15 ms 24032 KB Output is correct
9 Correct 13 ms 23892 KB Output is correct
10 Correct 14 ms 23952 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23764 KB Output is correct
2 Correct 14 ms 23820 KB Output is correct
3 Correct 13 ms 23896 KB Output is correct
4 Correct 12 ms 24016 KB Output is correct
5 Correct 13 ms 24032 KB Output is correct
6 Correct 14 ms 23952 KB Output is correct
7 Correct 17 ms 23936 KB Output is correct
8 Correct 15 ms 24032 KB Output is correct
9 Correct 13 ms 23892 KB Output is correct
10 Correct 14 ms 23952 KB Output is correct
11 Correct 51 ms 32020 KB Output is correct
12 Correct 65 ms 34244 KB Output is correct
13 Correct 86 ms 37324 KB Output is correct
14 Correct 118 ms 41036 KB Output is correct
15 Correct 113 ms 42052 KB Output is correct
16 Correct 100 ms 41292 KB Output is correct
17 Correct 100 ms 42948 KB Output is correct
18 Correct 95 ms 41292 KB Output is correct
19 Correct 101 ms 43980 KB Output is correct
20 Correct 70 ms 36160 KB Output is correct
21 Correct 67 ms 35752 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23764 KB Output is correct
2 Correct 14 ms 23820 KB Output is correct
3 Correct 13 ms 23896 KB Output is correct
4 Correct 12 ms 24016 KB Output is correct
5 Correct 13 ms 24032 KB Output is correct
6 Correct 14 ms 23952 KB Output is correct
7 Correct 17 ms 23936 KB Output is correct
8 Correct 15 ms 24032 KB Output is correct
9 Correct 13 ms 23892 KB Output is correct
10 Correct 14 ms 23952 KB Output is correct
11 Correct 51 ms 32020 KB Output is correct
12 Correct 65 ms 34244 KB Output is correct
13 Correct 86 ms 37324 KB Output is correct
14 Correct 118 ms 41036 KB Output is correct
15 Correct 113 ms 42052 KB Output is correct
16 Correct 100 ms 41292 KB Output is correct
17 Correct 100 ms 42948 KB Output is correct
18 Correct 95 ms 41292 KB Output is correct
19 Correct 101 ms 43980 KB Output is correct
20 Correct 70 ms 36160 KB Output is correct
21 Correct 67 ms 35752 KB Output is correct
22 Correct 1006 ms 46156 KB Output is correct
23 Correct 973 ms 44696 KB Output is correct
24 Correct 956 ms 44788 KB Output is correct
25 Correct 960 ms 49088 KB Output is correct
26 Correct 972 ms 45916 KB Output is correct
27 Correct 981 ms 44684 KB Output is correct
28 Correct 854 ms 29528 KB Output is correct
29 Correct 936 ms 39064 KB Output is correct
30 Correct 926 ms 39076 KB Output is correct
31 Correct 955 ms 39424 KB Output is correct
32 Correct 911 ms 42648 KB Output is correct