Cod sursa(job #2401085)

Utilizator BovisioNitica Ionut Bogdan Bovisio Data 9 aprilie 2019 13:35:17
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.49 kb
#include <cstdio>
#include <queue>
#include <vector>

#define INF 9999999

using namespace std;

int n,m,D[50002];

vector < pair < int, int > > L[50002];
priority_queue < pair < int, int > > Heap;

void Dijkstra(int start)
{
    int node,cost,info1,info2,sizeVecini;
    for(int i=1;i<=n;i++)
        D[i] = INF;
    D[start] = 1;

    Heap.push(make_pair(0, start));
    while(!Heap.empty())
    {
        cost = -Heap.top().first;
        node = Heap.top().second;
        Heap.pop();
        if(cost <= D[node])
        {
            sizeVecini = L[node].size();
            for(int i=0;i<sizeVecini;i++)
            {
                info1 = L[node][i].first;
                info2 = L[node][i].second;
                if(D[info1] > cost + info2)
                {
                    D[info1] = cost + info2;
                    //Heap.push({-D[info1], info1});
                    Heap.push(make_pair(-D[info1], info1));
                }
            }
        }
    }

}

int main()
{
    FILE *f = fopen("dijkstra.in","r");
    FILE *g = fopen("dijkstra.out","w");

    fscanf(f,"%d %d",&n,&m);

    int a,b,c;

    for(int i=1;i<=m;i++)
    {
        fscanf(f,"%d %d %d",&a,&b,&c);
        L[a].push_back({b,c});
    }
    //printf("crapa");
    Dijkstra(1);
    //printf("crapa2");
    for(int i=2;i<=n;i++)
    {
        if(D[i] != INF)
            fprintf(g,"%d ",D[i]);
        else
            fprintf(g,"0 ");
    }


    return 0;
}