Cod sursa(job #1457351)

Utilizator xraven78Eduard Mihes xraven78 Data 3 iulie 2015 11:44:44
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.69 kb
#include <fstream>
#include <vector>
#include <queue>
#define maxn 100010
using namespace std;

ifstream f("bfs.in");
ofstream g("bfs.out");

vector<int> a[maxn];
int n,m,start,cost[maxn];
queue<int> q;


void BFS(int st)
{
q.push(st);
for(int i=0;i<maxn;i++)
cost[i]=-1;
cost[st]=0;

int aux;
while(q.empty()==false)
{
    aux=q.front();
    q.pop();
for (int i=0;i<a[aux].size();i++)
{
    if(cost[a[aux][i]]==-1)
   {
       q.push(a[aux][i]);
       cost[a[aux][i]]=cost[aux]+1;
   }}}}


int main()
{
int x,y;
f>>n>>m>>start;
for(int i=0;i<m;i++)
{
    f>>x>>y;
    a[x].push_back(y);
}
BFS(start);
for(int i=1;i<=n;i++)
g<<" "<<cost[i];
return 0;
}