Cod sursa(job #1262966)

Utilizator pintilie.andreiPintilie pintilie.andrei Data 13 noiembrie 2014 19:23:33
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.64 kb
#include <fstream>
#include <queue>
#define INF 10000000
#include <vector>
#define NMAX 50010

using namespace std;

ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");

int n,m,ok;

queue <int> C;
vector< pair<int,int> > M[NMAX];
int use[NMAX],d[NMAX],tata[NMAX];

void bellmanford();
int cauta_cost(int,int);

int main()
{
    int i,x,y,c;
    fin >> n >> m;//nodul de start 1
    for(i=1;i<=m;i++)
    {
        fin >> x >> y >> c;
        M[x].push_back(make_pair(y,c));
    }
    bellmanford();
    if(ok==0)
        fout << "Ciclu negativ!\n";
    else
        for(i=2;i<=n;i++)
            fout << d[i] << ' ';
    return 0;
}

void bellmanford()
{
    int i,val,dim,cat;
    C.push(1);
    //pop
    //front
    use[1]=1;
    for(i=1;i<=n;i++)
    {
        d[i]=INF;
        tata[i]=0;
    }
    ok=1;
    d[1]=0;
    while(C.size()!=0 && ok==1)
    {
        val=C.front();
        C.pop();
        dim=M[val].size();
        for(i=0;i<dim;i++)
        {
            if(d[M[val][i].first]>d[val]+M[val][i].second)
            {
                //imbunatatesc
                d[M[val][i].first]=d[val]+M[val][i].second;
                C.push(M[val][i].first);
                use[M[val][i].first]++;
                tata[M[val][i].first]=val;
                if(use[M[val][i].first]==n)
                {
                    ok=0;
                    break;
                }
            }
        }
    }
}


int cauta_cost(int a,int b)
{
    int i,dim=M[a].size();
    for(i=0;i<dim;i++)
        if(M[a][i].first==b)
            return M[a][i].second;
    return INF;
}