Cod sursa(job #2505865)

Utilizator mara_anghelinaAnghelina Mara mara_anghelina Data 7 decembrie 2019 11:31:34
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.3 kb
#include <iostream>
#include <fstream>
#include <set>
#include <vector>

using namespace std;

const int MAXN = 50041;
const int INF = 0x3f3f3f3f;

ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

int n,m;
struct vecin{
    int y;
    int cost;
    bool operator<(const vecin& other) const
    {
        if(cost != other.cost)
            return cost < other.cost;
        return y < other.y;
    }
};

vector<vecin>graf[MAXN];
set<vecin>q;
int dmin[MAXN];

void citire()
{
    f>>n>>m;
    for(int i=0;i<m;i++)
    {
        int x,y,c;
        f>>x>>y>>c;
        graf[x].push_back({y,c});
    }
}
void rez()
{
    for(int i=2;i<=n;i++)
        dmin[i] = INF;
    q.insert({1,0});
    while(!q.empty())
    {
        int top = q.begin()->y;
        q.erase(q.begin());
        for(const vecin& v : graf[top])
        {
            int nouCost = dmin[top] + v.cost;
            if(dmin[v.y] > nouCost)
            {
                if(dmin[v.y] != INF)
                    q.erase({v.y, dmin[v.y]});
                dmin[v.y] = nouCost;
                q.insert({v.y, dmin[v.y]});
            }
        }
    }
}
void afisare()
{
    for(int i=2;i<=n;i++)
        g<<dmin[i]<<" ";
}

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