Submission #42314

#	Time	Username	Problem	Language	Result	Execution time	Memory
42314		IvanC	Senior Postmen (BOI14_postmen)	C++14	55 / 100	667 ms	76280 KiB

postmen

#include <bits/stdc++.h>
using namespace std;
typedef vector<int> vi;
const int MAXN = 5*1e5 + 10;
int N,M,e1[MAXN],e2[MAXN],e3[MAXN],marcado[MAXN],ptr[MAXN];
vi grafo[MAXN],pilha;
vector<vi> resposta;
int dfs(int v){
	//printf("DFS %d\n",v);
	marcado[v] = 1;
	for(;ptr[v] < grafo[v].size();ptr[v]++){
		int idx = grafo[v][ptr[v]];
		if(e3[idx] == 1) continue;
		e3[idx] = 1;
		int u = (e1[idx] != v) ? (e1[idx]) : (e2[idx]);
		if(marcado[u]){
			marcado[v] = 0;
			pilha.push_back(v);
			return u;
		}
		int ret = dfs(u);
		if(ret == v){
			pilha.push_back(v);
			resposta.push_back(pilha);
			pilha.clear();
		}
		else{
			marcado[v] = 0;
			pilha.push_back(v);
			return ret;
		}
	}
	marcado[v] = 0;
	pilha.clear();
	return -1;
}
int main(){
	scanf("%d %d",&N,&M);
	for(int i = 1;i<=M;i++){
		scanf("%d %d",&e1[i],&e2[i]);
		grafo[e1[i]].push_back(i);
		grafo[e2[i]].push_back(i);
	}
	for(int i = 1;i<=N;i++){
		dfs(i);
	}
	for(int i = 0;i<resposta.size();i++){
		for(int j : resposta[i]) printf("%d ",j);
		printf("\n");
	}
	return 0;
}

Compilation message (stderr)

postmen.cpp: In function 'int dfs(int)':
postmen.cpp:11:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(;ptr[v] < grafo[v].size();ptr[v]++){
       ~~~~~~~^~~~~~~~~~~~~~~~~
postmen.cpp: In function 'int main()':
postmen.cpp:47:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0;i<resposta.size();i++){
                ~^~~~~~~~~~~~~~~~
postmen.cpp:38:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&N,&M);
  ~~~~~^~~~~~~~~~~~~~~
postmen.cpp:40:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d",&e1[i],&e2[i]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 38 / 38
• Subtask 2: 17 / 17
• Subtask 3: 0 / 45