Cod sursa(job #2274838)

Utilizator JigsawKillerPetrescu Alexandru JigsawKiller Data 2 noiembrie 2018 16:19:11
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.41 kb
#include <utility>
#include <queue>
#include <vector>
#include <fstream>
#define NMAX 50000
#define inf 1000000000

using namespace std;

vector<pair<int, int>>g[NMAX + 1];
int d[NMAX + 1], marked[NMAX + 1];
priority_queue<pair<int, int>>heap;

void dijkstra(int start)
{
    int i;

    heap.push({0, start});

    while(!heap.empty())
    {
        pair<int, int>node = heap.top();
        heap.pop();
        pair<int, int>vecin;
        marked[node.second] = 1;

        for(i = 0; i < g[node.second].size(); i++)
        {
            if(!marked[g[node.second][i].first])
            {
                vecin.first = g[node.second][i].second + -node.first;
                vecin.second = g[node.second][i].first;

                if(d[vecin.second] > vecin.first)
                {
                    d[vecin.second] = vecin.first;

                    heap.push({-vecin.first, vecin.second});
                }
            }
        }
    }
}

int main()
{
    int n, m, i, j, x, y, z;

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

    fin >> n >> m;

    for(i = 1; i <= m; i++)
    {
        fin >> x >> y >> z;

        g[x].push_back({y, z});
    }

    d[1] = 0;

    for(i = 2; i <= n; i++)d[i] = inf;

    dijkstra(1);

    for(i = 2; i <= n; i++)
    {
        if(d[i] == inf)d[i] = 0;
        fout << d[i] << " ";
    }
    return 0;
}