Cod sursa(job #2675942)

Utilizator lucian666Vasilut Lucian lucian666 Data 22 noiembrie 2020 23:03:08
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.45 kb


#include <iostream>
#include <fstream>
#include <algorithm>
#include <vector>
#include <utility>
#include <queue>

#define INF 0x3f3f3f3f

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


typedef pair<int,int> pr;

void dijkstra(int startNode, vector<int>& dist, vector<vector<pair<int,int> > >& g)
{

    priority_queue<pr, vector<pr>, greater<pr> > minHeap;
    minHeap.push(make_pair(0, startNode));
    dist[startNode] = 0;

    while(minHeap.size())
    {
        pr node = minHeap.top();
        minHeap.pop();

        int nod = node.second;
        int cost = node.first;

        for(int i = 0; i < g[nod].size(); ++i)
        {
            int vecin = g[nod][i].first;
            int muchieDis = g[nod][i].second;

            if(dist[vecin] > dist[nod] + muchieDis)
            {
                dist[vecin] = dist[nod] + muchieDis;
                minHeap.push(make_pair(dist[vecin], vecin));
            }
        }
    }
}


int main()
{
    int n, m;
    in >> n >> m;

    vector<vector< pair<int,int> > > g(n + 2, vector<pair<int,int> >());

    for(int x, y, cost; m; --m)
    {
        in >> x >> y >> cost;
        g[x].push_back(make_pair(y, cost));
    }

    vector<int> dist(n + 2, INF);
    int startNode = 1;
    dijkstra(startNode, dist, g);
    for(int i = 2; i<=n; ++i)
        out << (dist[i] == INF ? 0 : dist[i]) << " ";

    return 0;
}