Cod sursa(job #1197698)

Utilizator tdr_drtTdr Drt tdr_drt Data 13 iunie 2014 13:58:10
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include<fstream>
#include<vector>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int n,m,i,x,y,j,s,k;
vector <int> l[100002];
int c[1000003];
int v[100002];

void read()
{
    ifstream f("bfs.in");
    f>>n>>m>>s;
    for(int i=1;i<=m;i++)
    {
        f>>x>>y;
        l[x].push_back(y);
    }
    f.close();
}



void bfs(int nod)
{
    int st,dr;
    st=1;
    dr=1;
    v[nod]=1;
    c[dr]=nod;
    while(st<=dr)
    {
       k=c[st];
       for(int i=0;i<l[k].size();i++)
       {
           if(v[l[k][i]]==0)
           {
             v[l[k][i]]=v[k]+1;
             c[++dr]=l[k][i];
           }
       }
       st++;
    }
}

void write()
{
    for(int i=1;i<=n;i++)
    g<<v[i]-1<<" ";
}

int main()
{
    read();
    bfs(s);
    write();
    return 0;
}