68 lines
2.0 KiB
Java
68 lines
2.0 KiB
Java
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package Sorts;
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import static Sorts.SortUtils.*;
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/**
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* The idea of Swap-Sort is to count the number m of smaller values (that are in
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* A) from each element of an array A(1...n) and then swap the element with the
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* element in A(m+1). This ensures that the exchanged element is already in the
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* correct, i.e. final, position. The disadvantage of this algorithm is that
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* each element may only occur once, otherwise there is no termination.
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*/
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public class SwapSort implements SortAlgorithm {
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@Override
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public <T extends Comparable<T>> T[] sort(T[] array) {
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int LENGTH = array.length;
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int index = 0;
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while (index < LENGTH - 1) {
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int amountSmallerElements = this.getSmallerElementCount(array, index);
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if (amountSmallerElements > 0 && index != amountSmallerElements) {
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T element = array[index];
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array[index] = array[amountSmallerElements];
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array[amountSmallerElements] = element;
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} else {
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index++;
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}
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}
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return array;
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}
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private <T extends Comparable<T>> int getSmallerElementCount(T[] array, int index) {
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int counter = 0;
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for (int i = 0; i < array.length; i++) {
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if (less(array[i], array[index])) {
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counter++;
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}
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}
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return counter;
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}
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public static void main(String[] args) {
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// ==== Int =======
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Integer[] a = { 3, 7, 45, 1, 33, 5, 2, 9 };
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System.out.print("unsorted: ");
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print(a);
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System.out.println();
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new SwapSort().sort(a);
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System.out.print("sorted: ");
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print(a);
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System.out.println();
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// ==== String =======
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String[] b = { "banana", "berry", "orange", "grape", "peach", "cherry", "apple", "pineapple" };
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System.out.print("unsorted: ");
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print(b);
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System.out.println();
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new SwapSort().sort(b);
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System.out.print("sorted: ");
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print(b);
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}
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}
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