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