Cod sursa(job #1503152)

Utilizator tothalToth Alexandru tothal Data 15 octombrie 2015 17:36:06
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.05 kb
/*Fiind dat un nod S, sa se determine, pentru fiecare nod X, numarul minim de arce ce trebuie parcurse pentru a ajunge din nodul sursa S la nodul X.
*/
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <cstring>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
vector<int>v[100005];
queue<int>q;
int n,m,x,s[100005];
void read()
{
    fin>>n>>m>>x;
    for(int i=0;i<m;i++)
    {
        int e,ee;
        fin>>e>>ee;
        //v[ee].push_back(e);
        v[e].push_back(ee);

    }
}
void BFS()
{
memset(s,-1,sizeof(s));
    s[x]=0;
    q.push(x);
    while(!q.empty())
    {
        int nod=q.front();q.pop();
        for(int i=0;i<v[nod].size();i++)
        {
            int vecin=v[nod][i];
            if(s[vecin]==-1)
            {
                s[vecin]=s[nod]+1;
                q.push(vecin);
            }
        }
    }
}
void print()
{
    int i;
    for(i=1;i<=n;i++)
        fout<<s[i]<<" ";
}
int main()
{
read();
BFS();
print();
return 0;
}