惠州网站搭建上海网站营销是什么
题目：
题解：
func countNumbersWithUniqueDigits(n int) int {if n == 0 {return 1}if n == 1 {return 10}ans, cur := 10, 9for i := 0; i < n-1; i++ {cur *= 9 - ians += cur}return ans
}
题目：
题解：
func countNumbersWithUniqueDigits(n int) int {if n == 0 {return 1}if n == 1 {return 10}ans, cur := 10, 9for i := 0; i < n-1; i++ {cur *= 9 - ians += cur}return ans
}