44 lines
1.1 KiB
Java
44 lines
1.1 KiB
Java
package Sorting;
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/**
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* an implementation of quick sort with three-way partitioning
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*/
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public class QuickSorterThreeWay extends Sorter{
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public QuickSorterThreeWay(String filename){
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super("quick sort (3-way partition)", filename);
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}
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void sort(){
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quickSort(0,numbers.length-1);
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}
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void quickSort(int lowIndex, int highIndex){
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if(compare(lowIndex,highIndex)<0){
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int pivot=numbers[highIndex];
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int lessThan = lowIndex;
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int greaterThan = highIndex;
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int i = greaterThan-1;
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while(i>=lessThan){
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int comp = compare(numbers[i], pivot);
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if(comp>0){
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swap(i, greaterThan);
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i--;
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greaterThan--;
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}
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else if(comp<0){
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swap(i, lessThan);
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lessThan++;
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}
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else{
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i--;
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}
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}
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quickSort(lowIndex, lessThan-1);
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quickSort(greaterThan+1, highIndex);
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}
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}
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} |