Files
2025-02-Numerical/lib/nr/k_and_r/recipes/hpsel.c
2025-09-12 18:55:25 +09:00

30 lines
526 B
C

void hpsel(m,n,arr,heap)
float arr[],heap[];
unsigned long m,n;
{
void sort();
void nrerror();
unsigned long i,j,k;
float swap;
if (m > n/2 || m < 1) nrerror("probable misuse of hpsel");
for (i=1;i<=m;i++) heap[i]=arr[i];
sort(m,heap);
for (i=m+1;i<=n;i++) {
if (arr[i] > heap[1]) {
heap[1]=arr[i];
for (j=1;;) {
k=j << 1;
if (k > m) break;
if (k != m && heap[k] > heap[k+1]) k++;
if (heap[j] <= heap[k]) break;
swap=heap[k];
heap[k]=heap[j];
heap[j]=swap;
j=k;
}
}
}
}