Cod sursa(job #1775026)

Utilizator cosminmaneaCosmin Manea cosminmanea Data 9 octombrie 2016 18:32:19
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.95 kb
#include <cstdio>
#include <vector>
#include <cstring>
#include <queue>

using namespace std;

vector <int> lv[100001];
queue <int> q;
int used[1000001],lenght[100001];

void bfs(int nod)
{
    int i;
    memset(used,-1,sizeof(used));
    q.push(nod);
    used[nod]=0;
    while(!q.empty())
    {
        for(i=0;i<lenght[q.front()];i++)
        {
            if(used[lv[q.front()][i]]==-1)
            {
                q.push(lv[q.front()][i]);
                used[q.back()]=used[q.front()]+1;
            }
        }
        q.pop();
    }
}

int main()
{
    FILE *f=fopen("bfs.in","r");
    FILE *g=fopen("bfs.out","w");
    int i,n,m,s;
    fscanf(f,"%d%d%d",&n,&m,&s);
    int x,y;
    for(i=1;i<=m;i++)
    {
        fscanf(f,"%d%d",&x,&y);
        lv[x].push_back(y);
    }
    for(i=1;i<=n;i++)
        lenght[i]=lv[i].size();
    bfs(s);
    for(i=1;i<=n;i++)
        fprintf(g,"%d ",used[i]);
    return 0;
}