Submission #832737

#	Time	Username	Problem	Language	Result	Execution time	Memory
832737		serifefedartar	Senior Postmen (BOI14_postmen)	C++17	100 / 100	441 ms	80052 KiB

postmen

#include <bits/stdc++.h>
using namespace std;
 
#define fast ios::sync_with_stdio(0);cin.tie(0);
typedef long long ll;
#define f first
#define s second
#define MOD 1000000007
#define LOGN 20
#define MAXN 300005
 
vector<vector<pair<int,int>>> graph;
vector<bool> active;
vector<int> pathVis;

int go_back = 0;
void dfs(int node, int parent) {
	pathVis[node] = true;
	for (auto u : graph[node]) {
		if (u.f == parent || !active[u.s])
			continue;
 
		if (pathVis[u.f]) {
			printf("%d ", u.f);
			go_back = u.f;
			active[u.s] = false;
		} else
			dfs(u.f, node);
 
		if (go_back) {
			if (go_back == node) {
				go_back = 0;
				active[u.s] = false;
				printf("\n");
				continue ;
			}
			printf("%d ", node);
			active[u.s] = false;
			pathVis[node] = false;
			return ;
		}
	}
	pathVis[node] = false;
}
 
int main() {
    int N, M, a, b;
    scanf("%d %d", &N, &M);
 
    graph = vector<vector<pair<int,int>>>(N+1, vector<pair<int,int>>());
    active = vector<bool>(M, true); 
    pathVis = vector<int>(N+1, false);
    for (int i = 0; i < M; i++) {
    	scanf("%d %d", &a, &b);
    	graph[a].push_back({b, i});
    	graph[b].push_back({a, i});
    }
 
    for (int i = 1; i <= N; i++)
    	dfs(i, i);
}

Compilation message (stderr)

postmen.cpp: In function 'int main()':
postmen.cpp:48:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |     scanf("%d %d", &N, &M);
      |     ~~~~~^~~~~~~~~~~~~~~~~
postmen.cpp:54:11: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |      scanf("%d %d", &a, &b);
      |      ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 38 / 38
• Subtask 2: 17 / 17
• Subtask 3: 45 / 45