Cod sursa(job #2964984)

Utilizator raileanu-alin-gabrielRaileanu Alin-Gabriel raileanu-alin-gabriel Data 14 ianuarie 2023 11:10:44
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.26 kb
#include <fstream>
#include <vector>
#include <queue>
const int NMAX=50005;

using namespace std;
ifstream fin("bellman.in");
ofstream fout("bellman.out");

vector< pair< int, int > > v[NMAX];
queue< pair< int, int > > q; //{cost, nod}
int dmin[NMAX], in[NMAX];
bool uz[NMAX];
int n, p, m;

void bellman(int);

int main()
{
    ios_base::sync_with_stdio(false);
    fin.tie(0);
    fout.tie(0);
    int i, a, b, c;
    fin>>n>>m;
    for(i=1; i<=m; i++)
    {
        fin>>a>>b>>c;
        v[a].push_back(make_pair(b, c));
    }
    for(i=2; i<=n; i++) dmin[i]=2e9;
    bellman(1);
    return 0;
}

void bellman(int nod)
{
    int i;
    pair <int, int> p;
    q.push({0, nod});
    while(!q.empty())
    {
        p=q.front();
        for(auto i:v[p.second])
        {
            if(dmin[i.first]>dmin[p.second]+i.second)
            {
                in[i.first]++;
                if(in[i.first]>=n+1)
                {
                    fout<<"Ciclu negativ!"<<'\n';
                    return;
                }
                dmin[i.first]=dmin[p.second]+i.second;
                q.push({dmin[i.first], i.first});
            }
        }
        q.pop();
    }
    for(i=2; i<=n; i++) fout<<dmin[i]<<' ';
    return;
}