import javax.swing.*;
import java.util.Random;
import java.util.Scanner;
public class RandExample {
public static void main(String[] args) {
int MethodChoice = Integer.parseInt(JOptionPane.showInputDialog("What method would you like to use to sort the random numbers" + "\n" + "1 - Selection Sort" + "\n" + "2 - Bubble Sort" + "\n" + "3 - Insertion Sort" + "\n" + "4 - Quick Sort"));
if (MethodChoice == 1) {
int iTotalCount = Integer.parseInt(JOptionPane.showInputDialog("What is the total number of integers?"));
int[] array = new int[iTotalCount];
Random randomGenerator = new Random();
for (int i = 0; i < iTotalCount; i++) {
array[i] = randomGenerator.nextInt(1001);
System.out.print(" " + array[i]);
}
System.out.println("\n---------------------------------");
selectionSort(array);
//print out sorted list
System.out.println("After sorting using the Selection Sort," + " the array is:");
for (int count = 0; count < array.length; count++) {
System.out.print(array[count] + " ");
}
} else if (MethodChoice == 2) {
int iTotalCount = Integer.parseInt(JOptionPane.showInputDialog("What is the total number of integers?"));
int[] array = new int[iTotalCount];
Random randomGenerator = new Random();
for (int i = 0; i < iTotalCount; i++) {
array[i] = randomGenerator.nextInt(1001);
System.out.print(" " + array[i]);
}
System.out.println("\n---------------------------------");
bubbleSort(array);
//print out sorted list
System.out.println("After sorting using the Bubble Sort,"
+ " the array is:");
for (int count = 0; count <array.length; count++) {
System.out.print(array[count] + " ");
}
} else if (MethodChoice == 3) {
int iTotalCount = Integer.parseInt(JOptionPane.showInputDialog("What is the total number of integers?"));
int[] array = new int[iTotalCount];
Random randomGenerator = new Random();
for (int i = 0; i < iTotalCount; i++) {
array[i] = randomGenerator.nextInt(1001);
System.out.print(" " + array[i]);
}
System.out.println("\n---------------------------------");
bubbleSort(array);
//print out sorted list
System.out.println("After sorting using the Insertion Sort,"
+ " the array is:");
for (int count = 0; count <array.length; count++) {
System.out.print(array[count] + " ");
}
} else if (MethodChoice == 4) {
int iTotalCount = Integer.parseInt(JOptionPane.showInputDialog("What is the total number of integers?"));
int[] array = new int[iTotalCount];
Random randomGenerator = new Random();
for (int i = 0; i < iTotalCount; i++) {
array[i] = randomGenerator.nextInt(1001);
System.out.print(" " + array[i]);
}
System.out.println("\n---------------------------------");
bubbleSort(array);
//print out sorted list
System.out.println("After sorting using the Quick Sort,"
+ " the array is:");
for (int count = 0; count <array.length; count++) {
System.out.print(array[count] + " ");
}
}
}
public static void quickSort(int data[], int low, int high) {
int partitionLoc;
if (low < high) {
partitionLoc = partition(data, low, high);
quickSort(data, low, partitionLoc - 1);
quickSort(data, partitionLoc + 1, high);
}
}
public static int partition(int data2[],int left,int right) {
boolean moveLeft = true;
int separator = data2[left];
while (left < right) {
if (moveLeft == true) {
while ((data2[right] >= separator) && (left < right)) {
right--;
}
data2[left] = data2[right];
moveLeft = false;
} else {
while ((data2[left] <= separator) && (left < right)) {
left++;
}
data2[right] = data2[left];
moveLeft = true;
}
}
data2[left] = separator;
return left;
}
public static void bubbleSort(int data[]) {
//Loop to control number of passes
for (int pass = 1; pass < data.length; pass++) {
//Loop to control # of comparisons for length of array-1
for (int element=0;element<data.length-1;element++) {
//compare side-by-side elements and swap them if
//first element is greater than second element
if (data[element] > data[element + 1]) {
swap(data, element, element + 1); //call swap method
}
}
}
}
public static void swapBubble(int array2[], int first, int second) {
int hold = array2[first];
array2[first] = array2[second];
array2[second] = hold;
}
public static void insertionSort(int data[]) {
int insert;
for (int next = 1; next < data.length; next++) {
insert = data[next];
int moveItem = next;
while (moveItem > 0 && data[moveItem - 1] > insert) {
data[moveItem] = data[moveItem - 1];
moveItem--;
}
data[moveItem] = insert;
}
}
public static void selectionSort(int data[]) {
int smallest;
for (int i = 0; i < data.length - 1; i++) {
smallest = i;
//see if there is a smaller number further in the array
for (int index = i + 1; index < data.length; index++) {
if (data[index] < data[smallest]) {
swap(data, smallest, index);
}
}
}
}
public static void swap(int array2[], int first, int second) {
int hold = array2[first];
array2[first] = array2[second];
array2[second] = hold;
}
}
我试过看但是它们用于列表，我想提示用户看看他们是否想要从升序或降序输出排序。我不太确定如何做到这一点，我已经看到使用反向的功能，但我不知道如何将其应用到我的代码中。
答案 0 :(得分：0)
您只需向后打印数组即可。
for(int i = array.length-1; i >= 0; i--)
System.out.print(array[i] + " ");