Sorting and Searching - Java Concepts - page 875

17 */
18 public void sort()
19 {
20 if (a.length <= 1 ) return ;
21 int [] first = new int [a.length / 2 ];
22 int [] second = new int [a.length -
first.length];
23 System.arraycopy(a, 0 , first, 0 ,
first.length);
24 System.arraycopy(a, first.length,
second, 0 , second.length);
25 MergeSorter firstSorter = new
MergeSorter(first);
26 MergeSorter secondSorter = new
MergeSorter(second);
27 firstSorter.sort();
28 secondSorter.sort();
29 merge(first, second);
30 }
31
32 /**
33 Merges two sorted arrays into the array managed by this
34 merge sorter.
35 @param first the first sorted array
36 @param second the second sorted array
37 */
38 private void merge( int [] first, int [] second)
39 {
40// Merge both halves into the temporary array
41
42 int iFirst = 0 ;
43// Next element to consider in the first array
44 int iSecond = 0 ;
45// Next element to consider in the second array
46 int j = 0 ;
47// Next open position in a
48
49// As long as neither iFirst nor iSecond past the end, move
50// the smaller element into a
51 while (iFirst < first.length && iSecond <
second.length)

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