Cod sursa(job #2189525)

Utilizator AndreiTudorSpiruAndrei Spiru AndreiTudorSpiru Data 28 martie 2018 15:51:30
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.75 kb
#include <fstream>
#include <queue>
#include <vector>
#include <climits>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
queue <int> c;
vector <int> v[100001];
int n,m,s,i,j,x,y,cost[100001];
int main()
{
    f>>n>>m>>s;
    for(i=1;i<=m;i++)
    {
        f>>x>>y;
        v[x].push_back(y);

    }
    for(i=1;i<=n;i++)
        cost[i]=INT_MAX;
    cost[s]=0;
    c.push(s);
    while(!c.empty())
    {
        x=c.front();
        for(j=0;j<v[x].size();j++)
        {
            if(cost[x]+1<cost[v[x][j]]){cost[v[x][j]]=cost[x]+1;c.push(v[x][j]);}
        }
        c.pop();
    }
    for(i=1;i<=n;i++)
    {
        if(cost[i]==INT_MAX)g<<-1<<" ";
        else g<<cost[i]<<" ";
    }
    return 0;
}