Cod sursa(job #2964923)

Utilizator raileanu-alin-gabrielRaileanu Alin-Gabriel raileanu-alin-gabriel Data 14 ianuarie 2023 10:01:44
Problema Algoritmul lui Dijkstra Scor 60
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.23 kb
#include <fstream>
#include <vector>
#include <set>
const int NMAX=50005;

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

vector< pair< int, int > > v[NMAX];
set< pair< int, int > > s; //{cost, nod}
int dmin[NMAX];
bool uz[NMAX];
int n, m;

void dijkstra(int);

int main()
{
    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;
    dijkstra(1);
    for(i=2; i<=n; i++)
    {
        if(dmin[i]==2e9) dmin[i]=0;
        fout<<dmin[i]<<' ';
    }
    return 0;
}

void dijkstra(int nod)
{
    pair <int, int> p;
    int cnt=n;
    s.insert({0, nod});
    cnt--;
    while(s.size() && cnt>0)
    {
        p=(*s.begin());
        if(uz[(p).second]==false)
        {
            uz[(p).second]=true;
            for(auto i:v[(p).second])
            {
                if(dmin[i.first]>dmin[(p).second]+i.second)
                {
                    dmin[i.first]=dmin[(p).second]+i.second;
                    s.insert(make_pair(dmin[i.first], i.first));
                }
            }
            cnt--;
        }
        s.erase(s.begin());
    }
}