Cod sursa(job #2365198)

Utilizator baranceanuBaranceanu Vlad baranceanu Data 4 martie 2019 12:31:18
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.39 kb
#include <fstream>
#include <queue>
#include <vector>
#define NMAX  50002
#define INF 5000000    // std::queue
using namespace std;
ifstream fin("bellmanford.in");
ofstream fout("bellmanford.out");
void citire();
bool belmmanford();
void afisare();
queue <int> coada;
int cmin[NMAX];
int uz[NMAX];
int nr[NMAX];
int n,m,start=1;
struct graf{int nod,val;};
vector <graf> g[NMAX];
int main ()
{
    citire();
    if(belmmanford())
    afisare();
    else
    {
        fout<<"Ciclu negativ!";
    }
  return 0;
}
void citire()
{
    int i,j;
    int a,b,c;
    fin>>n>>m;
    graf k;
    for(i=1;i<=m;i++)
    {
        fin>>a>>b>>c;
        k.val=c;
        k.nod=b;
        g[a].push_back(k);
    }
}
bool belmmanford()
{
    int i,x;
    coada.push(start);
    for(i=1;i<=n;i++)
    {
        cmin[i]=INF;
    }
    cmin[start]=0;
    while(!coada.empty())
    {
        x=coada.front();
        coada.pop();
        for(i=0;i<g[x].size();i++)
        {
            if(cmin[g[x][i].nod]>cmin[x]+g[x][i].val)
            {
                cmin[g[x][i].nod]=cmin[x]+g[x][i].val;
                nr[g[x][i].nod]++;
                if(nr[g[x][i].nod]>=n)
                    return 0;
                coada.push(g[x][i].nod);
            }
        }
    }
    return 1;
}
void afisare()
{
    int i;
    for(i=2;i<=n;i++)
        fout<<cmin[i]<<' ';
}