Cod sursa(job #2049098)

Utilizator marcudanfDaniel Marcu marcudanf Data 26 octombrie 2017 20:49:51
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.66 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <cstring>

using namespace std;

ifstream fin("bfs.in");
ofstream fout("bfs.out");

vector <int> v[100010];

int n,m,s,l;
int vecini[100010],len[100010],q[100010];

void bfs(int start){
	memset(len,-1,sizeof(len));
	len[start]=0;
	q[l++]=start;
	for(int i=0;i<=l;i++){
		for(int j=0;j<vecini[q[i]];j++){
			if(len[v[q[i]][j]]==-1){
				q[++l]=v[q[i]][j];
				len[q[l]]=1+len[q[i]];
			}
		}
	}
}

int main(){
	int x,y;
	fin>>n>>m>>s;
	for(int i=1;i<=m;i++){
		fin>>x>>y;
		v[x].push_back(y);
	}
	for(int i=1;i<=n;i++)
		vecini[i]=v[i].size();
	bfs(s);
	for(int i=1;i<=n;i++)
		fout<<len[i]<<" ";
	return 0;
}