Cod sursa(job #3238033)

Utilizator Her0ninjaDragos Rolland Her0ninja Data 15 iulie 2024 17:57:52
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.9 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <limits.h>

using namespace std;

void bfs(int start, vector<vector<int>>& z, vector<int>& t) {
    queue<int> q;
    q.push(start);
    t[start]=0;

    while (!q.empty()) {
        int c=q.front();
        q.pop();

        for (int s:z[c]) {
            if (t[s]==INT_MAX) {
                t[s]=t[c]+1;
                q.push(s);
            }
        }
    }
}

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

    int N,M,S;
    f>>N>>M>>S;

    vector<vector<int>> z(N+1);
    vector<int> t(N+1,INT_MAX);

    for (int i=0;i<M;i++) {
        int X,Y;
        f>>X>>Y;
        z[X].push_back(Y);
    }

    bfs(S,z,t);

    for (int i=1; i<=N;i++) {
        g<<(t[i]==INT_MAX ? -1:t[i])<< " ";
    }
    g<<endl;

    f.close();
    g.close();
    return 0;
}