32 lines
938 B
Java
32 lines
938 B
Java
package com.hithomelabs.princeton1.module8;
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import com.hithomelabs.princeton1.module5.AbstractCustomSorts;
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public class HeapSort<E> extends AbstractCustomSorts<E> {
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@Override
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public void sort(E[] arr) {
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int N = arr.length;
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E[] heapArr = (E[]) new Object[N+1];
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// * * to simplify we copy original array from
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System.arraycopy(arr, 0, heapArr, 1, N);
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// * * An array of size N holds a heap of size N-1
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coreSortingLogic(heapArr, N);
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System.arraycopy(heapArr, 1, arr, 0, N);
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}
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private void coreSortingLogic(E[] arr, int N) {
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// * * Converting array to max-heap an array in place
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for (int i = N/2; i >= 1; i--)
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Heap.sink(arr, i, N);
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// * * After converting to max-heap, in every iteration remove the max element of the heap
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while(N > 1){
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exch(arr, 1, N--);
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Heap.sink(arr, 1, N);
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}
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}
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}
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