Cod sursa(job #2549357)

Utilizator PandaChanTrusca Daria PandaChan Data 17 februarie 2020 17:10:35
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include <fstream>
#include <vector>
#include <set>
#define inf 0x3f3f3f3f
using namespace std;

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

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

vector <nod> graph[50005];
set <nod> s;
int n, m, viz[50005], nr[50005];
int dmin[50005];

void parcurg()
{
    for(int i=2; i<=n; i++)
        dmin[i]=inf;
    s.insert({0, 1});

    while(!s.empty())
    {
        int varf=s.begin()->vecin;
        s.erase(s.begin());

        for(const nod& v:graph[varf])
        {
            int nc=dmin[varf]+v.cost;
            if(dmin[v.vecin] > nc)
            {
                if(dmin[v.vecin] != inf)
                    s.erase({dmin[v.vecin], v.vecin});
                dmin[v.vecin]=nc;
                s.insert({dmin[v.vecin], v.vecin});
            }
        }
    }
}

int trans(int x)
{
    if(x==inf)
        return 0;
    return x;
}

int main()
{
    f>>n>>m;

    for(int i=1; i<=m; i++)
    {
        int x, y, c;
        f>>x>>y>>c;
        graph[x].push_back({c, y});
    }
    parcurg();
    for(int i=2; i<=n; i++)
        g<<trans(dmin[i])<<' ';

    return 0;
}