94 lines
2.4 KiB
Java
94 lines
2.4 KiB
Java
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/**
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*
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* @author Varun Upadhyay (https://github.com/varunu28)
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*
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*/
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class QuickSort {
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/**
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* This method implements the Generic Quick Sort
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*
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* @param array The array to be sorted
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* @param start The first index of an array
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* @param end The last index of an array
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* Sorts the array in increasing order
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**/
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public static <T extends Comparable<T>> void QS(T array[], int start, int end) {
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if (start < end) {
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int PIndex = partition(array, start, end);
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QS(array, start, PIndex - 1);
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QS(array, PIndex + 1, end);
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}
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}
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/**
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* This method finds the partition index for an array
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*
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* @param array The array to be sorted
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* @param start The first index of an array
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* @param end The last index of an array
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* Finds the partition index of an array
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**/
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public static <T extends Comparable<T>> int partition(T array[], int start, int end) {
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T pivot = array[end];
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int PIndex = start;
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for (int i=start;i<end;i++) {
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if (array[i].compareTo(pivot) <= 0) {
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swap(array, i, PIndex);
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PIndex++;
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}
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}
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swap(array, PIndex, end);
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return PIndex;
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}
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/**
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* This method swaps two elements of an array
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*
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* @param array The array to be sorted
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* @param initial The first element
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* @param fin The second element
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* Swaps initial and fin element
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**/
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public static <T extends Comparable<T>> void swap(T[] array, int initial, int fin) {
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T temp = array[initial];
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array[initial] = array[fin];
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array[fin] = temp;
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}
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// Driver Program
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public static void main(String[] args) {
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// For integer input
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int[] arr = {3,4,1,32,0,2,44,111,5};
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Integer[] array = new Integer[arr.length];
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for (int i=0;i<arr.length;i++) {
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array[i] = arr[i];
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}
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QS(array, 0, arr.length-1);
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//Output => 0 1 2 3 4 5 32 44 111
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for (int i=0;i<array.length;i++) {
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System.out.print(array[i] + " ");
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}
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System.out.println();
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// String Input
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String[] array1 = {"c", "a", "e", "b","d"};
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QS(array1, 0,array1.length-1);
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//Output => a b c d e
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for(int i=0; i<array1.length; i++)
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{
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System.out.print(array1[i]+"\t");
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}
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}
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}
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