Cod sursa(job #2999817)

Utilizator MihiBluBalau Mihai MihiBlu Data 11 martie 2023 15:51:18
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.92 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

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

bool inq[100010];
int n, m, s, d[100010];
vector <int> v[100010];
queue <pair <int, int> > q;

int main()
{
    f>>n>>m>>s;
    for(int i=1; i<=m; i++)
    {
        int x, y;
        f>>x>>y;
        v[x].push_back(y);
    }
    q.push(make_pair(s, 0));
    inq[s]=1;
    while(!q.empty())
    {
        int x=q.front().first;
        int cost=q.front().second;
        d[x]=cost;
        for(int i=0; i<v[x].size(); i++)
        {
            int vecin=v[x][i];
            if(inq[vecin]==0)
            {
                q.push(make_pair(vecin, cost+1));
                inq[vecin]=1;
            }
        }
        q.pop();
    }
    for(int i=1; i<=n; i++)
        if(d[i]==0 && i!=s)
            g<<"-1 ";
        else
            g<<d[i]<<" ";
    return 0;
}