Pagini recente » Statistici Teodor Stefu (Stefu_Teodor_Petre_322CC) | Cod sursa (job #213869) | Cod sursa (job #349940) | Cod sursa (job #286827) | Cod sursa (job #855809)
Cod sursa(job #855809)
#include <fstream>
#include <vector>
#define LS (p<<1)
#define RS ((p<<1)+1)
#define Ft (p>>1)
#define INF (1<<30)
#define NMAX 50004
using namespace std;
ifstream in("dijkstra.in");
ofstream out("dijkstra.out");
int N,M,D[NMAX];
vector<pair<int,int> > V[NMAX];
int Heap[NMAX<<1],Size;
void Down_Heap(int p)
{
int min = p,aux;
if( D[Heap[LS]] < D[Heap[min]])
min = LS;
if( D[Heap[RS]] < D[Heap[min]])
min = RS;
if(p != min)
aux = Heap[min],Heap[min] = Heap[p],Heap[p] = aux;
}
void Up_Heap(int p)
{
if(p&&D[Heap[p]] < D[Heap[Ft]])
{
int aux = Heap[p];
Heap[p] = Heap[Ft];
Heap[Ft] = aux;
Up_Heap(Ft);
}
}
void Push_Heap(int nod)
{
Heap[++Size] = nod;
Up_Heap(Size);
}
void Pop_Heap()
{
Heap[1] = Heap[Size--];
Down_Heap(1);
}
int main ()
{
int i,x,y,c;
in>>N>>M;
while(M--)
{
in>>x>>y>>c;
V[x].push_back(make_pair(y,c));
}
for(D[0] = -1,i=2;i<=N;i++)
D[i] = INF;
for(i = N;i;i--)
{
if(i>N/2)
Heap[++Size] = i;
else
Push_Heap(i);
}
while(Size)
{
x = Heap[1];
Pop_Heap();
for(i=0;i<V[x].size();i++)
{
y = V[x][i].first;
c = V[x][i].second;
if(D[y] > D[x]+c)
D[y] = D[y] = D[x]+c,Push_Heap(y);
}
}
for(i=2;i<=N;i++)
out<<(D[i]!= INF ? D[i] : 0)<<' ';
}