Cod sursa(job #2732157)

Utilizator HardtoPronouncePetcu David-Andrei HardtoPronounce Data 28 martie 2021 19:37:09
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.83 kb
#include <bits/stdc++.h>

using namespace std;

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

const int INF=1e9;

int n,m,s,x,y;
vector<int> v[100005];
int dist[100005];
queue<int> q;

void bfs()
{
    q.push(s);
    dist[s]=0;
    while(!q.empty())
    {
        int nod=q.front();
        q.pop();
        for (auto it:v[nod])
        {
            if (dist[it]>dist[nod]+1)
            {
                dist[it]=dist[nod]+1;
                q.push(it);
            }
        }
    }
}

int main()
{
    f>>n>>m>>s;
    for (int i=1; i<=m; i++)
    {
        f>>x>>y;
        v[x].push_back(y);
    }
    for (int i=1;i<=n;i++)
        dist[i]=INF;
    bfs();
    for (int i=1;i<=n;i++)
        if (dist[i]==INF)
            g<<-1<<" ";
        else
            g<<dist[i]<<" ";

    return 0;
}