Cod sursa(job #2514843)

Utilizator Catalin_GriuGriu Catalin Catalin_Griu Data 26 decembrie 2019 22:38:32
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb
#include <bits/stdc++.h>
#define NMAX 50005
#define INF 0x3f3f3f3f

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

typedef pair<int, int> pp;
int n, m;
vector< pp > v[NMAX];
int d[NMAX];

void dijkstra(int nod)
{
    //priority_queue < pp, vector<pp>, greater<pp> > pq;
    set<pp> h;
    h.insert(make_pair(0, nod));

    //pq.push(make_pair(0, nod));
    int in, from, to , cost;
    memset(d, INF, sizeof(d));
    d[nod] = 0;

    while(!h.empty())
    {
        auto k = h.begin();
        h.erase(k);
        from = k->second;
        //tie(in, from) = pq.top();
        //pq.pop();
        for(auto i: v[from])
        {
            tie(to, cost) = i;
            if(d[to]>d[from]+cost)
            {
                if(d[to]!=INF)
                    h.erase(h.find(make_pair(d[to], to)));
                d[to] = d[from] + cost;
                h.insert(make_pair(d[to], to));
                //pq.push(make_pair(d[to], to));
            }
        }


    }

}

int main()
{
    fin>>n>>m;
    int x, y, w;

    for(int i=0; i<m; i++)
    {
        fin>>x>>y>>w;
        v[x].push_back(make_pair(y, w));
    }

    dijkstra(1);
    for(int i =2; i<=n; i++)
    {
        if(d[i]==INF)
            d[i] = 0;
        fout<<d[i]<<' ';
    }

    return 0;
}