c# - 如何从递增的整数生成重复序列

Question

我需要一个函数，它将输入数字输入 int.Max 并给我一个 0 到 12 之间的数字 - 所以 1,2,3,4,5,6,7,8,9,10,11 是有效数字。

我想过按下面的方式做，但我想一定有更好的方法吧？

private static int GetNumberBetweenZeroAndTweleve(int inputNumber)
{
    int result = 1;
    for (int i = 1; i < inputNumber; i++)
    {
        // something elegant to calculate a number
        result++;
        if (result == 12)
            result = 1;
    }

    return result;
}

示例输入=>输出:

1 => 1
2 => 2
3 => 3
4 => 4
5 => 5
6 => 6
7 => 7
8 => 8
9 => 9
10 => 10
11 => 11
12 => 1
13 => 2
14 => 3

等等

Answer 1

您不需要任何循环(在inputNumber 较大的情况下可能昂贵:int.MaxValue 是 2147483647) 但是

 private static int GetNumberBetweenZeroAndTweleve(int inputNumber) {
   return inputNumber <= 0
     ? 1
     : (inputNumber - 1) % 11 + 1;
 }

测试:

var report = string.Join(Environment.NewLine, Enumerable
  .Range(1, 14)
  .Select(n => $"{n,2} => {GetNumberBetweenZeroAndTweleve(n),2}"));

Console.Write(report);

结果:

 1 =>  1
 2 =>  2
 3 =>  3
 4 =>  4
 5 =>  5
 6 =>  6
 7 =>  7
 8 =>  8
 9 =>  9
10 => 10
11 => 11
12 =>  1
13 =>  2
14 =>  3