Cod sursa(job #2175266)

Utilizator filip.mihalutMihalut Filip filip.mihalut Data 16 martie 2018 16:20:22
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.14 kb
#include <bits/stdc++.h>
#define Nmax 50005

using namespace std;

ifstream f ("dijkstra.in");
ofstream g ("dijkstra.out");

int d[Nmax],n,m,i,x,y,cost,nod,l,c,next_nod,INF = 0x3f3f3f3f;
set < pair < int,int > > heap;
vector < pair < int,int > > v[Nmax];

int main()
{
    f >> n >> m;
    for(i = 1; i <= m; i++)
    {
        f >> x >> y >> c;
        v[x].push_back({y,c});
    }

    heap.insert({0,1});

    memset(d, INF, sizeof(d));
    d[1] = 0;

    while(not heap.empty())
    {
        nod = heap.begin() -> second;
        heap.erase(heap.begin());

        for(i = 0,l = v[nod].size(); i < l; i++)
        {
            next_nod = v[nod][i].first;
            cost = v[nod][i].second;
            if(d[next_nod] > d[nod] + cost)
            {
                if(d[next_nod] != INF)
                    heap.erase(heap.find({d[next_nod],next_nod}));
                d[next_nod] = d[nod] + cost;
                heap.insert({d[next_nod],next_nod});
            }
        }

    }

    for(i = 2; i <= n; i++)
        if(d[i] != INF)
            g << d[i] << " ";
        else g << 0 << " ";
    return 0;
}