Cod sursa(job #2505752)

Utilizator elenaisaiaElena Isaia elenaisaia Data 7 decembrie 2019 10:45:03
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <climits>
#include <queue>

using namespace std;

int n,m,cost[50005],ok[50005],ceva=1;
vector<pair<int,int> >g[50005];
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > >q;

void citire()
{
    ifstream fin("dijkstra.in");
    fin>>n>>m;
    int x,y,c;
    for(int i=0;i<m;i++)
    {
        fin>>x>>y>>c;
        g[x].push_back(make_pair(y,c));
    }
    for(int i=2;i<=n;i++)
        cost[i]=INT_MAX/2;
    cost[1]=0;
}

void dij()
{
    q.push(make_pair(1,0));
    ok[1]=1;
    while(!q.empty())
    {
        int c=q.top().first;
        q.pop();
        ok[c]=0;
        for(auto &v:g[c])
            if(cost[v.first]>cost[c]+v.second)
            {
                cost[v.first]=cost[c]+v.second;
                if(!ok[v.first])
                {
                    q.push(make_pair(v.first,cost[v.first]));
                    ok[v.first]=1;
                }
            }
    }
}

void afisare()
{
    ofstream fout("dijkstra.out");
    for(int i=2;i<=n;i++)
        if(cost[i]==INT_MAX/2)
            cost[i]=0;
    for(int i=2;i<=n;i++)
        fout<<cost[i]<<" ";
}

int main()
{
    citire();
    dij();
    afisare();
    return 0;
}