refactor: cleanup CombSort (#5303)

refactor: cleanup CombSort

Co-authored-by: Alex Klymenko <alx@alx.com>
This commit is contained in:
Alex Klymenko
2024-08-02 09:06:45 +02:00
committed by GitHub
parent 5113101e5d
commit fccd141014
2 changed files with 39 additions and 116 deletions

View File

@ -16,76 +16,57 @@ package com.thealgorithms.sorts;
* @see SortAlgorithm * @see SortAlgorithm
*/ */
class CombSort implements SortAlgorithm { class CombSort implements SortAlgorithm {
private static final double SHRINK_FACTOR = 1.3;
// To find gap between elements /**
private int nextGap(int gap) { * Method to find the next gap
// Shrink gap by Shrink factor *
gap = (gap * 10) / 13; * @param gap the current gap
* @return the next gap value
*/
private int getNextGap(int gap) {
gap = (int) (gap / SHRINK_FACTOR);
return Math.max(gap, 1); return Math.max(gap, 1);
} }
/** /**
* Function to sort arr[] using Comb * Method to sort the array using CombSort
* *
* @param arr - an array should be sorted * @param arr the array to be sorted
* @return sorted array * @param <T> the type of elements in the array
* @return the sorted array
*/ */
@Override @Override
public <T extends Comparable<T>> T[] sort(T[] arr) { public <T extends Comparable<T>> T[] sort(T[] arr) {
int size = arr.length; int gap = arr.length;
// initialize gap
int gap = size;
// Initialize swapped as true to make sure that loop runs
boolean swapped = true; boolean swapped = true;
// Keep running while gap is more than 1 and last iteration caused a swap
while (gap != 1 || swapped) { while (gap != 1 || swapped) {
// Find next gap gap = getNextGap(gap);
gap = nextGap(gap); swapped = performSwaps(arr, gap);
// Initialize swapped as false so that we can check if swap happened or not
swapped = false;
// Compare all elements with current gap
for (int i = 0; i < size - gap; i++) {
if (SortUtils.less(arr[i + gap], arr[i])) {
// Swap arr[i] and arr[i+gap]
SortUtils.swap(arr, i, i + gap);
swapped = true;
}
}
} }
return arr; return arr;
} }
// Driver method /**
public static void main(String[] args) { * Method to perform the swapping of elements in the array based on the current gap
CombSort ob = new CombSort(); *
Integer[] arr = { * @param arr the array to be sorted
8, * @param gap the current gap
4, * @param <T> the type of elements in the array
1, * @return true if a swap occurred, false otherwise
56, */
3, private <T extends Comparable<T>> boolean performSwaps(final T[] arr, final int gap) {
-44, boolean swapped = false;
-1,
0,
36,
34,
8,
12,
-66,
-78,
23,
-6,
28,
0,
};
ob.sort(arr);
System.out.println("sorted array"); for (int i = 0; i < arr.length - gap; i++) {
SortUtils.print(arr); if (SortUtils.less(arr[i + gap], arr[i])) {
SortUtils.swap(arr, i, i + gap);
swapped = true;
}
}
return swapped;
} }
} }

View File

@ -1,66 +1,8 @@
package com.thealgorithms.sorts; package com.thealgorithms.sorts;
import static org.junit.jupiter.api.Assertions.assertArrayEquals; public class CombSortTest extends SortingAlgorithmTest {
@Override
import org.junit.jupiter.api.Test; SortAlgorithm getSortAlgorithm() {
return new CombSort();
/**
* @author Tabbygray (https://github.com/Tabbygray)
* @see CombSort
*/
public class CombSortTest {
private CombSort combSort = new CombSort();
@Test
public void combSortEmptyArray() {
Integer[] inputArray = {};
Integer[] outputArray = combSort.sort(inputArray);
Integer[] expectedOutput = {};
assertArrayEquals(outputArray, expectedOutput);
}
@Test
public void combSortSingleStringElement() {
String[] inputArray = {"Test"};
String[] outputArray = combSort.sort(inputArray);
String[] expectedArray = {"Test"};
assertArrayEquals(outputArray, expectedArray);
}
@Test
public void combSortStringArray() {
String[] inputArray = {"4gp8", "aBJ2", "85cW", "Pmk9", "ewZO", "meuU", "RhNd", "5TKB", "eDd5", "zzyo"};
String[] outputArray = combSort.sort(inputArray);
String[] expectedArray = {"4gp8", "5TKB", "85cW", "Pmk9", "RhNd", "aBJ2", "eDd5", "ewZO", "meuU", "zzyo"};
assertArrayEquals(outputArray, expectedArray);
}
@Test
public void combSortIntegerArray() {
Integer[] inputArray = {36, 98, -51, -23, 66, -58, 31, 25, -30, 40};
Integer[] outputArray = combSort.sort(inputArray);
Integer[] expectedArray = {-58, -51, -30, -23, 25, 31, 36, 40, 66, 98};
assertArrayEquals(outputArray, expectedArray);
}
@Test
public void combSortDoubleArray() {
Double[] inputArray = {0.8335545399, 0.9346214114, 0.3096396752, 0.6433840668, 0.3973191975, 0.6118850724, 0.0553975453, 0.1961108601, 0.6172800885, 0.1065247772};
Double[] outputArray = combSort.sort(inputArray);
Double[] expectedArray = {
0.0553975453,
0.1065247772,
0.1961108601,
0.3096396752,
0.3973191975,
0.6118850724,
0.6172800885,
0.6433840668,
0.8335545399,
0.9346214114,
};
assertArrayEquals(outputArray, expectedArray);
} }
} }