Cod sursa(job #643321)

Utilizator laurionLaurentiu Ion laurion Data 3 decembrie 2011 14:16:08
Problema Algoritmul lui Dijkstra Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 1.34 kb
//Bellman Ford (in loc de dijkstra) - 100p
#include<cstdio>
#include<iostream>
#include<algorithm>
#include<queue>
#include<cstring>
#include<vector>
using namespace std;

struct muchie
{
    int vec,cost;
};

vector <muchie> G[50000+10];
int d[50000+10];
bool InQueue[50000+10];

inline void bellmanford()
{
    memset(d,0x3f,sizeof(d));
    memset(InQueue,false,sizeof(InQueue));
    queue<int> Q;

    d[1]=0;
    InQueue[1]=true;
    Q.push(1);
    //for(int i=1;i<n;++i)
    while(!Q.empty())
    {
        int nod=Q.front();
        InQueue[nod]=false;
        Q.pop();
        for(vector<muchie>::iterator it=G[nod].begin(),stop=G[nod].end();it<stop;++it)
        {
            if( d[it->vec] > d[nod] + it->cost && !InQueue[it->vec])
            {
                d[it->vec] = d[nod] + it->cost;
                Q.push( it->vec );
                InQueue[it->vec]=true;
            }
        }

    }

}
int main()
{
    freopen("dijkstra.in","rt",stdin);
    freopen("dijkstra.out","wt",stdout);

    int n,m;

    cin>>n>>m;

    for(int i=1;i<=m;++i)
    {
        int from,to,cost;
        cin>>from>>to>>cost;
        G[from].push_back((muchie){to,cost});
    }
    bellmanford();

    for(int i=2;i<=n;++i)
        cout<<((d[i]==0x3f3f3f3f)?0:d[i])<<' ';
    putchar('\n');

    return 0;
}