Cod sursa(job #2502089)

Utilizator 0SiSBesliu Radu-Stefan 0SiS Data 30 noiembrie 2019 13:00:15
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.13 kb
#include <fstream>
#include <vector>
#include <queue>

#define INF 2147483647

using namespace std;

typedef pair < int, int > iPair;

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

int n, m, x, y, weight, dist[50001];

vector < vector < pair < int, int > > > edge(50001);
priority_queue < iPair, vector < iPair >, greater < iPair > > pq;

void dijkstra(int start)
{
    dist[1] = 0;
    for(int i = 2; i <= n; ++i)
    {
        dist[i] = INF;
    }
    pq.push({0, start});
    while(!pq.empty())
    {
        int u = pq.top().second;
        pq.pop();
        for(int i = 0; i < edge[u].size(); ++i)
        {
            int w = edge[u][i].first;
            int v = edge[u][i].second;
            if(dist[v] > dist[u] + w)
            {
                dist[v] = dist[u] + w;
                pq.push({dist[v], v});
            }
        }
    }
}

int main()
{
    f >> n >> m;
    for(int i = 1; i <= m; ++i)
    {
        f >> x >> y >> weight;
        edge[x].push_back({weight, y});
    }
    dijkstra(1);
    for(int i = 2; i <= n; ++i)
    {
        g << dist[i] << " ";
    }
}