Cod sursa(job #2680399)

Utilizator darisavuSavu Daria darisavu Data 3 decembrie 2020 14:05:47
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <bits/stdc++.h>

using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
vector<int>v[100005];
queue< pair<int,int> >q;
int viz[100005],n,m,s,x,y;
void bfs(int x)
{
    int nod,dist;
    q.push({x,0});
    viz[x]=1;
    while(!q.empty())
    {
        nod=q.front().first;
        dist=q.front().second;
        for(int i=0;i<v[nod].size();i++)
        {
            if(viz[v[nod][i]]==0)
            {
                viz[v[nod][i]]=dist+1;
                q.push({v[nod][i],dist+1});
            }
        }
        q.pop();
    }
}
int main()
{
    f>>n>>m>>s;
    for(int i=1;i<=m;i++)
    {
        f>>x>>y;
        v[x].push_back(y);
    }
    bfs(s);
    for(int i=1;i<=n;i++)
    {
        if(i==s) g<<"0 ";
        else if(viz[i]==0) g<<"-1 ";
        else g<<viz[i]<<" ";
    }
    return 0;
}