Cod sursa(job #2384977)

Utilizator kywyPApescu tiGEriu kywy Data 21 martie 2019 13:14:35
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <cstdio>
#include <algorithm>
#include <queue>
#include <vector>
using namespace std;

FILE* in=fopen("bfs.in", "r");
FILE* out=fopen("bfs.out", "w");
int n, m, s, d[100007];
vector<int> vecini[1000007];
queue<int> q;

void bfs(int nod)
{
    d[nod]=1;
    while(!q.empty())
    {
        nod=q.front();
        q.pop();
        for(int i=0; i<vecini[nod].size(); ++i)
        {
            if(d[vecini[nod][i]]==0||d[vecini[nod][i]]>d[nod]+1)
            {
                d[vecini[nod][i]]=d[nod]+1;
                q.push(vecini[nod][i]);
            }
        }
    }
}

int main()
{
    fscanf(in, "%d%d%d", &n, &m, &s);
    for(int i=1; i<=m; ++i)
    {
        int x, y;
        fscanf(in, "%d%d", &x, &y);
        vecini[x].push_back(y);
    }
    q.push(s);
    bfs(s);
    for(int i=1; i<=n; ++i)
    {
        fprintf(out, "%d ", d[i]-1);
    }
}