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/* |
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* @test |
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* @synopsis Checks that a priority queue returns elements in sorted order across various operations |
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*/ |
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|
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import java.util.*; |
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|
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public class PriorityQueueSort { |
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|
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static class MyComparator implements Comparator<Integer> { |
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public int compare(Integer x, Integer y) { |
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int i = ((Integer)x).intValue(); |
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int j = ((Integer)y).intValue(); |
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if (i < j) return -1; |
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if (i > j) return 1; |
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return 0; |
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} |
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} |
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|
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public static void main(String[] args) { |
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int n = 10000; |
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if (args.length > 0) |
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n = Integer.parseInt(args[0]); |
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|
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List<Integer> sorted = new ArrayList<Integer>(n); |
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for (int i = 0; i < n; i++) |
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sorted.add(new Integer(i)); |
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List<Integer> shuffled = new ArrayList<Integer>(sorted); |
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Collections.shuffle(shuffled); |
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|
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Queue<Integer> pq = new PriorityQueue<Integer>(n, new MyComparator()); |
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for (Iterator<Integer> i = shuffled.iterator(); i.hasNext(); ) |
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pq.add(i.next()); |
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|
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List<Integer> recons = new ArrayList<Integer>(); |
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while (!pq.isEmpty()) |
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recons.add(pq.remove()); |
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if (!recons.equals(sorted)) |
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throw new RuntimeException("Sort test failed"); |
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|
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recons.clear(); |
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pq = new PriorityQueue<Integer>(shuffled); |
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while (!pq.isEmpty()) |
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recons.add(pq.remove()); |
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if (!recons.equals(sorted)) |
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throw new RuntimeException("Sort test failed"); |
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|
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// Remove all odd elements from queue |
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pq = new PriorityQueue<Integer>(shuffled); |
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for (Iterator<Integer> i = pq.iterator(); i.hasNext(); ) |
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if ((i.next().intValue() & 1) == 1) |
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i.remove(); |
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recons.clear(); |
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while (!pq.isEmpty()) |
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recons.add(pq.remove()); |
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|
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for (Iterator<Integer> i = sorted.iterator(); i.hasNext(); ) |
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if ((i.next().intValue() & 1) == 1) |
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i.remove(); |
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|
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if (!recons.equals(sorted)) |
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throw new RuntimeException("Iterator remove test failed."); |
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} |
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} |
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