华为机试题 火车进站

import java.util.Scanner;

public class Main {
	public static boolean judge(int a[], int n) {// 从头开始，判断其后比他小的元素是否为降序，若不是，则不是正确的出栈序列，，若遇到比他大的数，则把它当做标记
		int tag = a[0];
		int p = a[0];
		int i = 1;
		for (i = 1; i < n; i++) {
			if (a[i] > tag) {
				tag = a[i];
				p=tag;
			} else if (a[i] < p) {
				p = a[i];
			} else {
				break;
			}

		}
		if (i == n) {
			return true;
		} else {
			return false;
		}

	}

	public static int[] reverse(int[] a, int l, int r) {
		int t;
		while (l < r) {
			t = a[l];
			a[l] = a[r];
			a[r] = t;
			l++;
			r--;
		}
		return a;
	}

	public static void printZidianxu(int[] a, int n) {

		int p = 0;
		int temp;
		while (true) {
			int flag = 0;
			for (int i = n - 1; i >= 0; i--) {
				if (i - 1 < 0)
					break;
				if (a[i] > a[i - 1]) {
					p = i - 1;
					while (i < n && a[p] < a[i]) {
						i++;
					}

					int minmax = i < n ? i - 1 : n - 1;
					temp = a[minmax];
					a[minmax] = a[p];
					a[p] = temp;
					a = reverse(a, p + 1, n - 1);
					if (judge(a, n)) {//满足火车入栈出栈的顺序 输出
						for (int k = 0; k < n-1; k++) {
							System.out.print(a[k] + " ");
						}
						System.out.print(a[n-1]);
						System.out.println();
					}
					flag = 1;
					break;
				}
			}
			if (flag == 0) {
				break;
			}
		}
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = 0;
		while (sc.hasNext()) {
			n = sc.nextInt();
			int arr[] = new int[n];
			for (int i = 0; i < n; i++) {
				arr[i] = sc.nextInt();
			}

			for (int k = 0; k < n-1; k++) {
				System.out.print(arr[k]+" ");
			}
			System.out.print(arr[n-1]);
			System.out.println();
			printZidianxu(arr, n);
		}

	}

}