Cod sursa(job #2905160)

Utilizator Paul281881818818181991919191881818Draghici Paul Paul281881818818181991919191881818 Data 19 mai 2022 21:35:16
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.08 kb
#include <fstream>
#include <vector>
#include <queue>
#define N 100001
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
bool viz[N]; int cost[N];
vector<vector<int> > V(N);
void BFS(int x){
    queue<int> Q;

    Q.push(x);
    viz[x] = true;
    while(!Q.empty()){
        int nod = Q.front();
        for(int i=0; i<V[nod].size(); i++){
            int nxt = V[nod][i];
            if(!viz[nxt]){
                viz[nxt] = true;
                cost[nxt] = cost[nod] + 1;
                Q.push(nxt);
            }
        }
        Q.pop();
    }
}
int main()
{
    int n, m, s;
    fin >> n >> m >> s;
    for(int i=1; i<=m; i++){
        int x1, x2;
        fin >> x1 >> x2;
        V[x1].push_back(x2);
    }
    /*for(int i=1; i<=n; i++){
        for(int j=0; j<V[i].size(); j++)
            fout << V[i][j] << ' ';
        fout << '\n';
    }*/
    BFS(s);
    for(int i=1; i<=n; i++){
        if(cost[i] == 0 && i != s)
            fout << -1 << ' ';
        else
            fout << cost[i] << ' ';
    }
    return 0;
}