66 lines
1.1 KiB
Java
66 lines
1.1 KiB
Java
import java.util.*;
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public class MergeableHeap {
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static Random random = new Random();
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public static class Heap {
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int value;
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Heap left;
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Heap right;
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Heap(int value) {
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this.value = value;
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}
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}
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public static Heap merge(Heap a, Heap b) {
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if (a == null)
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return b;
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if (b == null)
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return a;
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if (a.value > b.value) {
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Heap t = a;
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a = b;
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b = t;
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}
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if (random.nextBoolean()) {
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Heap t = a.left;
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a.left = a.right;
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a.right = t;
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}
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a.left = merge(a.left, b);
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return a;
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}
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public static Heap add(Heap h, int value) {
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return merge(h, new Heap(value));
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}
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public static class HeapAndResult {
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Heap heap;
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int value;
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HeapAndResult(Heap h, int value) {
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this.heap = h;
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this.value = value;
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}
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}
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public static HeapAndResult removeMin(Heap h) {
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return new HeapAndResult(merge(h.left, h.right), h.value);
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}
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// Usage example
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public static void main(String[] args) {
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Heap h = null;
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h = add(h, 3);
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h = add(h, 1);
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h = add(h, 2);
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while (h != null) {
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HeapAndResult hv = removeMin(h);
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System.out.println(hv.value);
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h = hv.heap;
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}
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}
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}
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