Cod sursa(job #2569995)

Utilizator vladadAndries Vlad Andrei vladad Data 4 martie 2020 14:35:20
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.15 kb
#include<bits/stdc++.h>
#define fi first
#define sc second
#define ll long long
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int n, m;
vector<pair<int, int> >v[200001];
set<pair<ll, ll> >s;
ll dist[200001];
bool viz[200001];
void dijk(int nod)
{
    viz[nod]=1;
    for(int i=0; i<v[nod].size(); i++)
    {
        if(!viz[v[nod][i].fi])
        {
            viz[v[nod][i].fi]=1;
            dist[v[nod][i].fi]=dist[nod]+v[nod][i].sc;
            s.insert({dist[nod], v[nod][i].fi});
        }
        else if(dist[nod]+v[nod][i].sc<dist[v[nod][i].fi])
        {
            s.erase({dist[v[nod][i].fi], v[nod][i].fi});
            dist[v[nod][i].fi]=dist[nod]+v[nod][i].sc;
            s.insert({dist[v[nod][i].fi], v[nod][i].fi});
        }
    }
}
main()
{
    f>>n>>m;
    for(int i=1; i<=m; i++)
    {
        int x, y, cost;
        f>>x>>y>>cost;
        v[x].push_back({y, cost});
    }
    s.insert({0, 1});
    while(!s.empty())
    {
        int a=(*s.begin()).sc;
        s.erase(s.begin());
        dijk(a);
    }
    for(int i=2; i<=n; i++)
        g<<dist[i]<<' ';
    return 0;
}