Cod sursa(job #2682221)

Utilizator radubigColtos Radu radubig Data 8 decembrie 2020 08:15:58
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <bits/stdc++.h>

using namespace std;
ifstream in("dijkstra.in");
ofstream out("dijkstra.out");
const int lim = 50000;
const int INF = 2e9;

vector<pair<int, int>> l[lim+5]; //first -> nod, second -> cost muchie
int dist[lim+5];
bitset<lim+5> viz;
int n, m;

void Dijkstra(int sursa)
{
    for(int i=1; i<=n; i++)
        dist[i] = INF;
    priority_queue<pair<int, int>> pq; //first-> -dist[nod], second -> nod
    dist[sursa]=0;
    pq.push(make_pair(0, sursa));
    while(!pq.empty())
    {
        int nod = pq.top().second;
        pq.pop();
        if(viz[nod]==0)
        {
            viz[nod]=1;
            for(auto& i : l[nod])
            {
                int vecin = i.first;
                int cost = i.second;
                if(dist[nod] + cost < dist[vecin])
                {
                    dist[vecin] = dist[nod]+cost;
                    pq.push(make_pair(-dist[vecin], vecin));
                }
            }
        }
    }
}

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

    Dijkstra(1);

    for(int i=2; i<=n; i++)
        if(dist[i] != INF) out<<dist[i]<<' ';
        else out<<"0 ";
    return 0;
}