求详细的java主函数写法

发布网友发布时间：2022-05-05 20:59

共1个回答

热心网友时间：2022-06-28 02:25

import java.util.Scanner;

public class T {

  public static void main(String[] args) {
    System.out.println("请输入一个正整数：");
    Scanner scanner = new Scanner(System.in);
    int n = scanner.nextInt();
    Integer[] list = new Integer[n];
    System.out.printf("请输入%d个不相同的整数：\n", n);
    for (int i = 0; i < n; i++) {
      list[i] = scanner.nextInt();
    }
    scanner.close();
    System.out.println();
    System.out.println("全排列：");
    perm(list, 0, n);
  }

  public static void perm(Object[] list, int k, int m) {
    if (k == m) {
      for (int i = 0; i < m; i++)
        System.out.print(list[i] + " ");
      System.out.println();
    } else {
      for (int i = k; i < m; i++) {
        swap(list, k, i);
        perm(list, k + 1, m);
        swap(list, k, i);
      }
    }
  }

  private static void swap(Object[] list, int k, int i) {
    Object temp = list[k];
    list[k] = list[i];
    list[i] = temp;
  }
}