Cod sursa(job #2738475)

Utilizator cpopescu1Popescu Cristian cpopescu1 Data 5 aprilie 2021 22:00:43
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.35 kb
#include <bits/stdc++.h>
#define INF 0x3f3f3f3f
using namespace std;

ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");

int n,m;
vector<pair<int,int> > lista[50005];
int D[50005];
bool inq[50005];

void read()
{
    fin>>n>>m;
    int x,y,c;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>c;
        lista[x].push_back({y,c});
    }
}

struct compara
{
    bool operator()(int x,int y)
    {
        return D[x]>D[y];
    }
};
priority_queue<int,vector<int>,compara> q;

void Dijkstra(int start)
{
    for(int i=1;i<=n;i++)
    {
        D[i]=INF;
        inq[i]=0;
    }
    D[start]=0;
    inq[start]=1;
    q.push(start);
    while(!q.empty())
    {
        int nod=q.top();
        q.pop();
        inq[nod]=false;
        for(auto x:lista[nod])
        {
            int vecin=x.first;
            int cost=x.second;
            if(D[vecin]>D[nod]+cost)
            {
                D[vecin]=D[nod]+cost;
                if(!inq[vecin])
                {
                    inq[vecin]=1;
                    q.push(vecin);
                }
            }
        }
    }
    for(int i=2;i<=n;i++)
    {
        if(D[i]==INF)fout<<0<<" ";
        else fout<<D[i]<<" ";
    }
}




int main()
{
    ios::sync_with_stdio(0);
    fin.tie(0);
    read();
    Dijkstra(1);
    return 0;
}