Submission #343214

#	Time	Username	Problem	Language	Result	Execution time	Memory
343214		benedict0724	One-Way Streets (CEOI17_oneway)	C++17	0 / 100	2013 ms	492 KiB

oneway

#include <bits/stdc++.h>

using namespace std;

vector<int> adj[1002];
pair<int, int> road[1002];
pair<int, int> haveTo[1002];
bool visited[1002];
bool poss = false;

void dfs(int x, int s, int e, int g){
    visited[x] = true;
    if(x == g){
        poss = true;
        return;
    }
    for(auto u : adj[x]){
        if(!visited[u] && (x != e || u != s)){
            dfs(u, s, e, g);
            if(poss) return;
        }
    }
}

int main()
{
    int n, m;
    scanf("%d %d", &n, &m);
    for(int i=1;i<=m;i++){
        int s, e;
        scanf("%d %d", &s, &e);
        adj[s].push_back(e);
        adj[e].push_back(s);
        road[i] = {s, e};
    }
    int p;
    scanf("%d", &p);
    for(int i=1;i<=p;i++){
        int s, e;
        scanf("%d %d", &s, &e);
        haveTo[i] = {s, e};
    }

    for(int i=1;i<=m;i++){
        int s = road[i].first, e = road[i].second;
        bool toR = true, toL = true;
        for(int j=1;j<=p;j++){
            for(int k=1;k<=n;k++){
                visited[k] = false;
            }
            poss = false;
            dfs(haveTo[j].first, s, e, haveTo[j].second);
            if(!poss){
                toR = false;
            }
            for(int k=1;k<=n;k++){
                visited[k] = false;
            }
            poss = false;
            dfs(haveTo[j].first, e, s, haveTo[j].second);
            if(!poss){
                toL = false;
            }
        }

        if(toR && toL) printf("B");
        else if(toR) printf("R");
        else printf("L");
    }
}

Compilation message (stderr)

oneway.cpp: In function 'int main()':
oneway.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   28 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
oneway.cpp:31:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |         scanf("%d %d", &s, &e);
      |         ~~~~~^~~~~~~~~~~~~~~~~
oneway.cpp:37:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |     scanf("%d", &p);
      |     ~~~~~^~~~~~~~~~
oneway.cpp:40:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |         scanf("%d %d", &s, &e);
      |         ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 30
• Subtask 2: 0 / 30
• Subtask 3: 0 / 40