gistfile1.java

import java.util.*;

public class s401631741HW1 {
  public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);

    System.out.print("i = ");
    int number = scanner.nextInt();
    Random random = new Random();
    int[][] arr = new int[number][];

    for (int i = 0; i < number; i++) {
      arr[i] = generateString(random.nextInt(30) + 1);
    }

    System.out.print("\nOriginal:\n");

    for (int[] str : arr) {
      printString(str);
    }

    System.out.print("\nSorted:\n");

    for (int[] str : arr) {
      printString(sortString(str));
    }
  }

  private static int[] generateString(int length) {
    int[] str = new int[length];
    Random random = new Random();

    for (int i = 0; i < length; i++) {
      str[i] = random.nextInt(26) + 97;
    }

    return str;
  }

  private static int[] sortString(int[] str) {
    return quickSort(str, 0, str.length - 1);
  }

  private static void printString(int[] str) {
    for (int i = 0; i < str.length; i++) {
      System.out.print((char) str[i]);
    }

    System.out.println();
  }

  private static int[] quickSort(int[] arr, int left, int right) {
    if (right <= left) return arr;

    int pivotIndex = (left + right) / 2;
    int pivot = arr[pivotIndex];

    swap(arr, pivotIndex, right);

    int swapIndex = left;

    for (int i = left; i < right; i++) {
      if (arr[i] <= pivot) {
        swap(arr, i, swapIndex++);
      }
    }

    swap(arr, swapIndex, right);
    quickSort(arr, left, swapIndex - 1);
    quickSort(arr, swapIndex + 1, right);

    return arr;
  }

  private static void swap(int[] arr, int a, int b) {
    int tmp = arr[a];
    arr[a] = arr[b];
    arr[b] = tmp;
  }
}