求整数n的各位数字之和，并判断n是几位数，以及判断是否为素数，求最大公约数，求阶乘，多种排序方法，以及数组转置的方法-Digits and integer n and n and determine the numbers that judgment is a prime number, and the greatest common divisor, factorial, and a variety of sorting methods, as well as the array transpose