输出一个任意数组的全排列

这是一个控制台应用程序，用于体系算法思想。

代码如下：

class Program
    {
        static void Main(string[] args)
        {
            Console.Write("请输入数字长度：");
            int n = Convert.ToInt32(Console.ReadLine());
            int[] A1 = new int[n];
            for (int i = 0; i < n; i++)
            {
                Console.Write($"请输入第{i + 1}个数：");
                A1[i] = Convert.ToInt32(Console.ReadLine());
            }
            Console.WriteLine("结果：");
            PrintFullPermutation(A1);
            Console.ReadKey();
        }


        /// <summary>
        /// 输出一个数组的全排列
        /// </summary>
        /// <param name="array"></param>
        private static void PrintFullPermutation(int[] array)
        {
            //0.合法性校验
            if (array == null || array.Length == 0)
            {
                return;
            }
            //1.复制一个新数组：修改时在临时数组中修改
            int[] temp = new int[array.Length];
            for (int i = 0; i < array.Length; i++)
            {
                temp[i] = array[i];
            }
            //2.将新数组升序排列
            int itemp;
            for (int i = 0; i < temp.Length; i++)
            {
                for (int j = i; j < temp.Length; j++)
                {
                    itemp = array[i];
                    array[i] = array[j];
                    array[j] = itemp;
                }
            }
            //3.依次寻找并打印全排序
            PrintArray(temp);
            while (!isDesc(temp))
            {
                FindNextArray(temp);
                PrintArray(temp);
            }
        }
        /// <summary>
        /// 打印数组
        /// </summary>
        /// <param name="array">数组</param>
        private static void PrintArray(int[] array)
        {
            for (int i = 0; i < array.Length; i++)
            {
                Console.Write(array[i].ToString() + '\t');
            }
            Console.WriteLine();
        }
        /// <summary>
        /// 判断一个数组内元素是否降序排列
        /// </summary>
        /// <param name="array">数组</param>
        /// <returns></returns>
        private static bool isDesc(int[] array)
        {
            int temp = array[0];
            for (int i = 1; i < array.Length; i++)
            {
                if (array[i] > array[i - 1])
                {
                    return false;
                }
            }
            return true;
        }
        /// <summary>
        /// 找到下一组排列
        /// </summary>
        /// <param name="array"></param>
        private static void FindNextArray(int[] array)
        {
            //1.找出数组的最大值
            int max = array[0];
            for (int i = 1; i < array.Length; i++)
            {
                if (max < array[i])
                {
                    max = array[i];
                }
            }
            //2.从后向前找：找到第一组后数大于前数，以后数位置为signer
            int signer = array.Length - 1;
            for (int i = array.Length - 1; i > 0; i--)
            {
                if (array[i] > array[i - 1])
                {
                    signer = i;
                    break;
                }
            }
            //3.从signer向后找：找到大于且最接近于array[signer-1]的数array[t]
            int t = signer;
            for (int i = signer; i < array.Length; i++)
            {
                if (array[i] > array[signer - 1] && array[i] < max)
                {
                    t = i;
                    max = array[t];
                }
            }
            //4.将找到的array[t]和array[signer-1]互换
            int temp = array[t];
            array[t] = array[signer - 1];
            array[signer - 1] = temp;
            //5.为signer之后的元素升序排序
            for (int i = signer; i < array.Length; i++)
            {
                for (int j = i + 1; j < array.Length; j++)
                {
                    if (array[i] > array[j])
                    {
                        temp = array[i];
                        array[i] = array[j];
                        array[j] = temp;
                    }
                }
            }
        }
    }