Cod sursa(job #1052700)

Utilizator Maxim97Maxim Andrei Maxim97 Data 11 decembrie 2013 18:13:41
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp Status done
Runda Arhiva educationala Marime 1.41 kb
#include <fstream>
#define nmax 50005
#include <vector>
#include <queue>
#define inf 250000000
#include <cstdio>
#include <utility>

using namespace std;

FILE *in,*o;

int n,m,x,y,c;
vector< pair<int, int> > graf[nmax];
queue <int> C;
int dmin[nmax],nr[nmax],pred[nmax];

void cit()
{
    int i;
    in=fopen("bellmanford.in","r");
    fscanf(in,"%d%d",&n,&m);
    for(i=1; i<=m; i++)
    {
        fscanf(in,"%d%d%d",&x,&y,&c);
        graf[x].push_back(make_pair(y,c));
    }
}

int bellmanford()
{
    int x,y,c;
    unsigned int i;
    for(i=2; i<=n; i++)
    {
        dmin[i]=inf;
        pred[i]=1;
    }
    C.push(1);
    nr[1]++;
    while(!C.empty())
    {
        x=C.front();
        C.pop();
        for(i=0; i<graf[x].size(); i++)
        {
            y=graf[x][i].first;
            c=graf[x][i].second;
            if(dmin[y]>dmin[x]+c)
            {
                dmin[y]=dmin[x]+c;
                pred[y]=x;
                nr[y]++;
                C.push(y);
                if(nr[y]==n)
                    return 0;
            }
        }
    }
    return 1;
}

void afis()
{
    int i;
    for(i=2; i<=n; i++)
        fprintf(o,"%d ",dmin[i]);
    fprintf(o,"\n");
}

int main()
{
    cit();
    o=fopen("bellmanford.out","w");
    if(bellmanford()==0)
        fprintf(o,"Circuit negativ!\n");
    else
        afis();
    return 0;
}