Cod sursa(job #1890580)

Utilizator SmitOanea Smit Andrei Smit Data 23 februarie 2017 12:46:03
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include <bits/stdc++.h>
#define INF 2000000000

using namespace std;

int n,m;
int d[50003];
bitset<50003>viz;
vector< pair<int,int> >L[50003];

void Citire()
{
    int i,x,y,c;
    ifstream fin("dijkstra.in");
    fin>>n>>m;
    for(i=1;i<=m;++i)
    {
        fin>>x>>y>>c;
        L[x].push_back({y,c});
    }
    fin.close();
}

void Dijkstra(int start)
{
    priority_queue< pair<int,int> >q;
    int i,x,y,c;
    unsigned int ui;
    for(i=1;i<=n;++i)///init
        d[i]=INF;
    d[start]=0;
    q.push({0,start});
    while(!q.empty())
    {
        x=q.top().second;
        q.pop();
        if(!viz[x])
        {
            viz[x]=1;
            for(ui=0;ui<L[x].size();++ui)
            {
                y=L[x][ui].first;
                c=L[x][ui].second;
                if(d[y] > d[x] + c)
                {
                    d[y] = d[x] + c;
                    q.push({-d[y],y});
                }
            }
        }
    }
}

void Afisare()
{
    int i;
    ofstream fout("dijkstra.out");
    for(i=2;i<=n;++i)
        fout<<d[i]<<" ";
    fout<<"\n";
    fout.close();
}

int main()
{
    Citire();
    Dijkstra(1);
    Afisare();
    return 0;
}