クイックソートアルゴリズムの実装. Java

#java #素早い #選別

Java

import java.util.Arrays;

class Quicksort {

static int partition(int array[], int low, int high) {
    
    int pivot = array[high];
    
    int i = (low - 1);

for (int j = low; j < high; j++) {
      if (array[j] <= pivot) {

i++;

int temp = array[i];
        array[i] = array[j];
        array[j] = temp;
      }

}

int temp = array[i + 1];
    array[i + 1] = array[high];
    array[high] = temp;

return (i + 1);
  }

static void quickSort(int array[], int low, int high) {
    if (low < high) {

int pi = partition(array, low, high);
      
      quickSort(array, low, pi - 1);

quickSort(array, pi + 1, high);
    }
  }
}

class Main {
  public static void main(String args[]) {

int[] data = { 8, 7, 2, 1, 0, 9, 6 };
    System.out.println("Unsorted Array");
    System.out.println(Arrays.toString(data));

int size = data.length;

Quicksort.quickSort(data, 0, size - 1);

System.out.println("Sorted Array in Ascending Order ");
    System.out.println(Arrays.toString(data));
  }
}

Output result

Unsorted Array
[8, 7, 2, 1, 0, 9, 6]
Sorted Array in Ascending Order
[0, 1, 2, 6, 7, 8, 9]

Java

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