Cod sursa(job #2870815)

Utilizator andreimocianAndrei Mocian andreimocian Data 12 martie 2022 16:29:12
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.38 kb
#include <iostream> 
#include <fstream> 
#include <vector>
#include <queue>

using namespace std; 

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

struct el
{
    int nod, cost;
    bool operator < (const el &A) const{
        return cost > A.cost;
    }
};

const int NMAX = 50005;
int n, m;
int dp[NMAX];
vector < el > L[NMAX];
priority_queue < el > Q;

inline void citire()
{
    el w;
    int x, y, z;
    fin >> n >> m;
    for(int i = 1; i <= m; ++i)
    {
        fin >> x >> y >> z;
        w.cost = z;
        w.nod = y;
        L[x].push_back(w);
    }
}

inline void Dijkstra()
{
    for(int i = 2; i <= n; ++i)
    {
        dp[i] = 1e9;
    }
    el w, w2;
    w2.nod = 1;
    w2.cost = 0;
    Q.push(w2);
    while(!Q.empty())
    {
        w = Q.top();
        Q.pop();
        for(auto it : L[w.nod])
        {
            if(dp[it.nod] > dp[w.nod] + it.cost)
            {
                dp[it.nod] = dp[w.nod] + it.cost;
                w2.nod = it.nod;
                w2.cost = dp[it.nod];
                Q.push(w2);
            }
        }
    }
}

inline void afisare()
{
    for(int i = 2; i <= n; ++i)
    {
        if(dp[i] == 1e9)
            fout << 0 << " ";
        else
            fout << dp[i] << " ";
    }
}

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