oj.uz

Submission #692228

# Submission time Handle Problem Language Result Execution time Memory
692228 2023-02-01T08:26:30 Z Quan2003 One-Way Streets (CEOI17_oneway) C++17
100 / 100
 146 ms 43604 KB 
#include<bits/stdc++.h>
#include<iostream>
using namespace std;
typedef long long ll;
typedef long double ld;
const int N = 5e5 + 5;
int up[21][N + 1];
int dp[N + 1],ds[N + 1];
int a[N + 1];
int n,m,q;
vector<pair<int,int>>tadj[N + 1];
vector<int>adj[N + 1];
char ans[N + 1]; 
int trs,dsz,psz;
vector<pair<int,int>>edges; 
vector<pair<int,int>>bridges; 
int cnt; 
bool vis[N + 1],use[N + 1],brid[N + 1]; 
int st[N + 1],low[N + 1];
int comp[N + 1];
int fa[N + 1];
int find(int u){
     if(u == fa[u]) return u;
     return fa[u] = find(fa[u]);
}
void unite(int u,int v){
     u = find(u); v = find(v);
     if(u == v) return;
     if(comp[u] > comp[v]) swap(u,v); 
     comp[v] += comp[u]; 
     fa[u] = v;
}
void dfs(int u,int p){
    a[u] = low[u] = ++dsz;
    for(int i = 0; i < tadj[u].size(); i++){
        auto x = tadj[u][i];
        int v = x.first;
        if(v == p) continue;
        if(!a[v]){
            dfs(v,u);
            low[u] = min(low[u] , low[v]);
            if(low[v] > a[u]) brid[x.second] = 1, bridges.push_back({u,v}); 
        }
        else low[u] = min(a[v] , low[u]);
    }
}
void dfs_calc(int u,int p){
    vis[u] = 1; 
    for(int i = 0; i < adj[u].size(); i++){
        auto v = adj[u][i]; 
        if(vis[v]) continue;
        ds[v] = ds[u] + 1; 
        dfs_calc(v,u);
        dp[u] += dp[v];
    }
     ///cout<<u<<; dp[u]<<' '<<dp[p]<<endl; 
} 
int main(){
     scanf("%d%d",&n,&m);
     for(int i = 1; i <= n; i++) fa[i] = i, comp[i] = 1; 
     for(int i = 0; i < m; i++){
         int u,v; scanf("%d%d",&u,&v);
         tadj[u].push_back({v,i});
         tadj[v].push_back({u,i}); 
         edges.push_back({u,v}); 
     }
     for(int i = 1; i <= n; i++){
          if(!a[i]) dfs(i,0); 
     }
     for(int i = 0; i < edges.size(); i++){
          if(brid[i]) continue;
          unite(edges[i].first,edges[i].second); 
     }
     for(int i = 1; i <= n; i++) find(i); 
     for(int i = 0; i < bridges.size(); i++){
          int u = bridges[i].first; int v = bridges[i].second;
          //cout<<fa[u]<<' '<<fa[v]<<endl; 
          adj[fa[u]].push_back(fa[v]);
          adj[fa[v]].push_back(fa[u]);
     }
     scanf("%d",&q); 
     for(int i = 0; i < q; i++){
          int x,y ; scanf("%d%d",&x,&y); 
          dp[fa[x]]++;
          dp[fa[y]]--;
     } 
     for(int i = 1; i <= n; i++) if(!vis[i]) dfs_calc(i,0); 
     for(int i = 0; i < edges.size(); i++){
           int u = edges[i].first; int v = edges[i].second;
           if(fa[u] == fa[v]) cout<<'B'; 
           else{
                u = fa[u]; v = fa[v]; 
               //if(i == 14) cout<<ds[fa[u]]<<' '<<ds[fa[v]]<<endl; 
                if(ds[u] > ds[v]){
                      if(dp[u] == 0) cout<<'B';
                      else if(dp[u] > 0) cout<<'R'; 
                      else cout<<'L'; 
                }
                if(ds[u] < ds[v]){
                      if(dp[v] == 0) cout<<'B'; 
                      else if(dp[v] > 0) cout<<'L'; 
                      else cout<<'R'; 
                }
           }
     }
     return 0; 
}

Compilation message

oneway.cpp: In function 'void dfs(int, int)':
oneway.cpp:35:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |     for(int i = 0; i < tadj[u].size(); i++){
      |                    ~~^~~~~~~~~~~~~~~~
oneway.cpp: In function 'void dfs_calc(int, int)':
oneway.cpp:49:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |     for(int i = 0; i < adj[u].size(); i++){
      |                    ~~^~~~~~~~~~~~~~~
oneway.cpp: In function 'int main()':
oneway.cpp:70:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |      for(int i = 0; i < edges.size(); i++){
      |                     ~~^~~~~~~~~~~~~~
oneway.cpp:75:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |      for(int i = 0; i < bridges.size(); i++){
      |                     ~~^~~~~~~~~~~~~~~~
oneway.cpp:88:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |      for(int i = 0; i < edges.size(); i++){
      |                     ~~^~~~~~~~~~~~~~
oneway.cpp:59:11: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |      scanf("%d%d",&n,&m);
      |      ~~~~~^~~~~~~~~~~~~~
oneway.cpp:62:24: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |          int u,v; scanf("%d%d",&u,&v);
      |                   ~~~~~^~~~~~~~~~~~~~
oneway.cpp:81:11: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   81 |      scanf("%d",&q);
      |      ~~~~~^~~~~~~~~
oneway.cpp:83:26: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |           int x,y ; scanf("%d%d",&x,&y);
      |                     ~~~~~^~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23764 KB Output is correct
2 Correct 12 ms 23852 KB Output is correct
3 Correct 17 ms 23888 KB Output is correct
4 Correct 16 ms 23960 KB Output is correct
5 Correct 16 ms 23924 KB Output is correct
6 Correct 13 ms 23900 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 12 ms 23892 KB Output is correct
9 Correct 12 ms 23892 KB Output is correct
10 Correct 11 ms 23812 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 12 ms 23852 KB Output is correct
3 Correct 17 ms 23888 KB Output is correct
4 Correct 16 ms 23960 KB Output is correct
5 Correct 16 ms 23924 KB Output is correct
6 Correct 13 ms 23900 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 12 ms 23892 KB Output is correct
9 Correct 12 ms 23892 KB Output is correct
10 Correct 11 ms 23812 KB Output is correct
11 Correct 54 ms 30500 KB Output is correct
12 Correct 54 ms 31904 KB Output is correct
13 Correct 58 ms 33632 KB Output is correct
14 Correct 81 ms 35216 KB Output is correct
15 Correct 74 ms 35732 KB Output is correct
16 Correct 92 ms 36148 KB Output is correct
17 Correct 106 ms 38208 KB Output is correct
18 Correct 79 ms 36180 KB Output is correct
19 Correct 80 ms 39796 KB Output is correct
20 Correct 52 ms 31232 KB Output is correct
21 Correct 64 ms 31432 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 12 ms 23852 KB Output is correct
3 Correct 17 ms 23888 KB Output is correct
4 Correct 16 ms 23960 KB Output is correct
5 Correct 16 ms 23924 KB Output is correct
6 Correct 13 ms 23900 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 12 ms 23892 KB Output is correct
9 Correct 12 ms 23892 KB Output is correct
10 Correct 11 ms 23812 KB Output is correct
11 Correct 54 ms 30500 KB Output is correct
12 Correct 54 ms 31904 KB Output is correct
13 Correct 58 ms 33632 KB Output is correct
14 Correct 81 ms 35216 KB Output is correct
15 Correct 74 ms 35732 KB Output is correct
16 Correct 92 ms 36148 KB Output is correct
17 Correct 106 ms 38208 KB Output is correct
18 Correct 79 ms 36180 KB Output is correct
19 Correct 80 ms 39796 KB Output is correct
20 Correct 52 ms 31232 KB Output is correct
21 Correct 64 ms 31432 KB Output is correct
22 Correct 114 ms 39372 KB Output is correct
23 Correct 99 ms 37168 KB Output is correct
24 Correct 108 ms 37276 KB Output is correct
25 Correct 105 ms 43604 KB Output is correct
26 Correct 106 ms 38804 KB Output is correct
27 Correct 146 ms 37256 KB Output is correct
28 Correct 52 ms 27868 KB Output is correct
29 Correct 73 ms 31908 KB Output is correct
30 Correct 79 ms 32400 KB Output is correct
31 Correct 87 ms 32400 KB Output is correct
32 Correct 106 ms 36908 KB Output is correct