Cod sursa(job #1889624)

Utilizator alex.craciunCraciun Alexandru alex.craciun Data 22 februarie 2017 20:08:50
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.05 kb
#include <iostream>
#include <vector>
#include <cstdio>
#include <queue>
# define nmx 100020
using namespace std;
vector <int> lv[nmx];
int n,m,s;
int d[nmx],used[nmx];
void citire( )
{
    int x,y;
    FILE *f=fopen("bfs.in","r");
    fscanf(f,"%d%d%d",&n,&m,&s);
    for(int i =1;i<=m;i++)
        {
            fscanf(f,"%d%d",&x,&y);
            if(x!=y)
            lv[x].push_back(y);
        }

    for(int i=1;i<=n;i++)
        d[i]=-1;
}
queue <int> q;

void rez( )
{
    q.push(s);
    d[s]=0;
    used[s]=1;

    while(!q.empty())
    {
        int nc =q.front();
        q.pop();
        int dmin=d[nc];
        vector <int> :: iterator ii;
        for(ii=lv[nc].begin();ii!=lv[nc].end();ii++)
            if(!used[*ii])
            {
                used[*ii]=1;
                d[*ii]=dmin+1;
                q.push(*ii);
            }

    }

}

int main()
{
     citire( );
     rez();
     FILE *f1=fopen("bfs.out","w");
     for(int i=1;i<=n;i++)
        fprintf(f1,"%d ",d[i]);
    return 0;
}