JavaAlgorithms/Sorts/TreeSort.java

114 lines
3.3 KiB
Java

package Sorts;
import static Sorts.SortUtils.print;
import java.util.List;
/**
* <h1> Implementation of the Tree Sort algorithm</h1>
*
* <p>
* Tree Sort: A sorting algorithm which constructs a Binary Search Tree
* using the unsorted data and then outputs the data by inorder traversal
* of the tree.
*
* Reference: https://en.wikipedia.org/wiki/Tree_sort
* </p>
*
* @author Madhur Panwar (https://github.com/mdrpanwar)
*/
public class TreeSort implements SortAlgorithm {
@Override
public <T extends Comparable<T>> T[] sort(T[] unsortedArray) {
return doTreeSortArray(unsortedArray);
}
@Override
public <T extends Comparable<T>> List<T> sort(List<T> unsortedList) {
return doTreeSortList(unsortedList);
}
private <T extends Comparable<T>> T[] doTreeSortArray(T[] unsortedArray) {
// create a generic BST tree
DataStructures.Trees.BSTRecursiveGeneric<T> tree = new DataStructures.Trees.BSTRecursiveGeneric<T>();
// add all elements to the tree
for(T element: unsortedArray) {
tree.add(element);
}
// get the sorted list by inorder traversal of the tree
List<T> sortedList = tree.inorderSort();
// add the elements back to the initial array
int i = 0;
for(T element: sortedList) {
unsortedArray[i++] = element;
}
// return the array
return unsortedArray;
}
private <T extends Comparable<T>> List<T> doTreeSortList(List<T> unsortedList) {
// create a generic BST tree
DataStructures.Trees.BSTRecursiveGeneric<T> tree = new DataStructures.Trees.BSTRecursiveGeneric<T>();
// add all elements to the tree
for(T element: unsortedList) {
tree.add(element);
}
// get the sorted list by inorder traversal of the tree and return it
return tree.inorderSort();
}
public static void main(String[] args) {
TreeSort treeSort = new TreeSort();
// ==== Integer Array =======
System.out.println("Testing for Integer Array....");
Integer[] a = { 3, -7, 45, 1, 343, -5, 2, 9 };
System.out.print(String.format("%-10s", "unsorted: "));
print(a);
a = treeSort.sort(a);
System.out.print(String.format("%-10s", "sorted: "));
print(a);
System.out.println();
// ==== Integer List =======
System.out.println("Testing for Integer List....");
List<Integer> intList = List.of(3, -7, 45, 1, 343, -5, 2, 9);
System.out.print(String.format("%-10s", "unsorted: "));
print(intList);
intList = treeSort.sort(intList);
System.out.print(String.format("%-10s", "sorted: "));
print(intList);
System.out.println();
// ==== String Array =======
System.out.println("Testing for String Array....");
String[] b = { "banana", "berry", "orange", "grape", "peach", "cherry", "apple", "pineapple" };
System.out.print(String.format("%-10s", "unsorted: "));
print(b);
b = treeSort.sort(b);
System.out.print(String.format("%-10s", "sorted: "));
print(b);
System.out.println();
// ==== String List =======
System.out.println("Testing for String List....");
List<String> stringList = List.of("banana", "berry", "orange", "grape", "peach", "cherry", "apple", "pineapple");
System.out.print(String.format("%-10s", "unsorted: "));
print(stringList);
stringList = treeSort.sort(stringList);
System.out.print(String.format("%-10s", "sorted: "));
print(stringList);
}
}