Cod sursa(job #2302879)

Utilizator iarinatudorTudor Iarina Maria iarinatudor Data 15 decembrie 2018 11:14:26
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.23 kb
#include <iostream>
#include <fstream>
#include <climits>
#include <queue>
#include <vector>

using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
int dp[50005],ok[50005],n,m;
vector< pair<int, int> >G[50005];

priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > Q;
void citire()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        int x,y,c;
        fin>>x>>y>>c;
        G[x].push_back({y,c});
    }
    for(int i=2; i<=n; i++)
        dp[i]=INT_MAX/2;
}

void dijkstra()
{
    dp[1]=0;
    Q.push({0,1});
    ok[1]=0;
    while(!Q.empty())
    {
        int x=Q.top().second;
        Q.pop();
        if(ok[x]==0)
        {
            for(auto &v:G[x])
            {
                int y=v.first;
                int cost=v.second;
                if(dp[y]>dp[x]+cost)
                {
                    dp[y]=dp[x]+cost;
                    Q.push({dp[y],y});
                }
            }
            ok[x]=1;
        }

    }
}
void afish()
{
    for(int i=2; i<=n; i++)
        if(dp[i]!=INT_MAX/2)fout<<dp[i]<<" ";
    else
        fout<<"0";
}
int main()
{
    citire();
    dijkstra();
    afish();
    return 0;
}