oj.uz

Submission #674943

# Submission time Handle Problem Language Result Execution time Memory
674943 2022-12-26T16:21:29 Z guagua0407 One-Way Streets (CEOI17_oneway) C++17
100 / 100
 275 ms 37468 KB 
/*
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#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end() 
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

const int mxn=1e5+5;
vector<int> adj[mxn];
vector<int> sccadj[mxn];
map<pair<int,int>,int> mp;
vector<int> st;
int order[mxn],low[mxn];
int depth[mxn];
int val[mxn];
vector<bool> visited(mxn,false);
int scc[mxn];
int sccnt=0;
int cnt=1;
vector<pair<int,int>> bridge;
vector<pair<int,int>> edges;

void dfs(int v,int p){
    order[v]=low[v]=cnt;
    cnt++;
    st.push_back(v);
    for(auto u:adj[v]){
        if(u==p and mp[{u,v}]==1) continue;
        if(order[u]){
            low[v]=min(low[v],order[u]);
        }
        else{
            dfs(u,v);
            low[v]=min(low[v],low[u]);
            if(low[u]==order[u]){
                bridge.push_back({v,u});
                sccnt++;
                while(st.back()!=u){
                    scc[st.back()]=sccnt;
                    st.pop_back();
                }
                scc[st.back()]=sccnt;
                st.pop_back();
            }
        }
    }
    if(p==-1){
        sccnt++;
        while(st.size()){
            scc[st.back()]=sccnt;
            st.pop_back();
        }
    }
}

void dfs2(int v,int p){
    visited[v]=true;
    if(p!=-1) depth[v]=depth[p]+1;
    for(auto u:sccadj[v]){
        if(u==p or visited[u]) continue;
        dfs2(u,v);
        val[v]+=val[u];
    }
}

int main() {_
    //setIO("wayne");
    int n,m;
    cin>>n>>m;
    for(int i=0;i<m;i++){
        int a,b;
        cin>>a>>b;
        edges.push_back({a,b});
        adj[a].push_back(b);
        adj[b].push_back(a);
        mp[{a,b}]++;
        mp[{b,a}]++;
    }
    for(int i=1;i<=n;i++){
        if(!scc[i]){
            dfs(i,-1);
        }
        //cout<<scc[i]<<' ';
    }
    for(int i=0;i<m;i++){
        if(scc[edges[i].f]!=scc[edges[i].s]){
            sccadj[scc[edges[i].f]].push_back(scc[edges[i].s]);
            sccadj[scc[edges[i].s]].push_back(scc[edges[i].f]);
        }
    }
    int q;
    cin>>q;
    for(int i=0;i<q;i++){
        int a,b;
        cin>>a>>b;
        val[scc[a]]++;
        val[scc[b]]--;
    }
    for(int i=1;i<=sccnt;i++){
        if(!visited[i]){
            dfs2(i,-1);
        }
    }
    for(auto v:edges){
        if(scc[v.f]==scc[v.s]){
            cout<<'B';
        }
        else{
            if(depth[scc[v.f]]>depth[scc[v.s]]){
                if(val[scc[v.f]]==0){
                    cout<<'B';
                }
                else if(val[scc[v.f]]>0){
                    cout<<'R';
                }
                else{
                    cout<<'L';
                }
            }
            else{
                if(val[scc[v.s]]==0){
                    cout<<'B';
                }
                else if(val[scc[v.s]]>0){
                    cout<<'L';
                }
                else{
                    cout<<'R';
                }
            }
        }
    }
    return 0;
}
//maybe its multiset not set

Compilation message

oneway.cpp: In function 'void setIO(std::string)':
oneway.cpp:20:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
oneway.cpp:21:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5044 KB Output is correct
3 Correct 4 ms 5176 KB Output is correct
4 Correct 5 ms 5204 KB Output is correct
5 Correct 4 ms 5308 KB Output is correct
6 Correct 4 ms 5204 KB Output is correct
7 Correct 4 ms 5332 KB Output is correct
8 Correct 4 ms 5204 KB Output is correct
9 Correct 4 ms 5204 KB Output is correct
10 Correct 4 ms 5204 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5044 KB Output is correct
3 Correct 4 ms 5176 KB Output is correct
4 Correct 5 ms 5204 KB Output is correct
5 Correct 4 ms 5308 KB Output is correct
6 Correct 4 ms 5204 KB Output is correct
7 Correct 4 ms 5332 KB Output is correct
8 Correct 4 ms 5204 KB Output is correct
9 Correct 4 ms 5204 KB Output is correct
10 Correct 4 ms 5204 KB Output is correct
11 Correct 192 ms 23564 KB Output is correct
12 Correct 198 ms 24912 KB Output is correct
13 Correct 248 ms 26516 KB Output is correct
14 Correct 264 ms 28064 KB Output is correct
15 Correct 245 ms 28572 KB Output is correct
16 Correct 242 ms 28844 KB Output is correct
17 Correct 211 ms 31420 KB Output is correct
18 Correct 252 ms 28932 KB Output is correct
19 Correct 207 ms 33468 KB Output is correct
20 Correct 168 ms 24568 KB Output is correct
21 Correct 150 ms 23544 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5044 KB Output is correct
3 Correct 4 ms 5176 KB Output is correct
4 Correct 5 ms 5204 KB Output is correct
5 Correct 4 ms 5308 KB Output is correct
6 Correct 4 ms 5204 KB Output is correct
7 Correct 4 ms 5332 KB Output is correct
8 Correct 4 ms 5204 KB Output is correct
9 Correct 4 ms 5204 KB Output is correct
10 Correct 4 ms 5204 KB Output is correct
11 Correct 192 ms 23564 KB Output is correct
12 Correct 198 ms 24912 KB Output is correct
13 Correct 248 ms 26516 KB Output is correct
14 Correct 264 ms 28064 KB Output is correct
15 Correct 245 ms 28572 KB Output is correct
16 Correct 242 ms 28844 KB Output is correct
17 Correct 211 ms 31420 KB Output is correct
18 Correct 252 ms 28932 KB Output is correct
19 Correct 207 ms 33468 KB Output is correct
20 Correct 168 ms 24568 KB Output is correct
21 Correct 150 ms 23544 KB Output is correct
22 Correct 249 ms 32520 KB Output is correct
23 Correct 216 ms 29856 KB Output is correct
24 Correct 275 ms 29908 KB Output is correct
25 Correct 237 ms 37468 KB Output is correct
26 Correct 232 ms 31944 KB Output is correct
27 Correct 250 ms 30036 KB Output is correct
28 Correct 58 ms 8748 KB Output is correct
29 Correct 184 ms 24892 KB Output is correct
30 Correct 177 ms 25140 KB Output is correct
31 Correct 225 ms 25824 KB Output is correct
32 Correct 157 ms 26920 KB Output is correct