编程之美---1的个数C#笨（效率低）方法实现

编程之美---1的个数C#笨（效率低）的方法实现

1. class Program
2.     {
3.         static void Main(string[] args)
4.         {
5.             Program p = new Program();
6.             Console.WriteLine(p.count_1_in_a_bounch_of_nums(13));
7.             Console.Read();
8.         }
10.         public int count_1_in_a_num(int num)
11.         {
12.             int count = 0;
13.             while (num != 0)
14.             {
15.                 
16.                 count += (num % 10) == 1 ? 1 : 0;
17.                 num /= 10;
18.             }
19.             return count;
20.         }
22.         public  int count_1_in_a_bounch_of_nums(int end)
23.         {
24.             int count = 0;
25.             for (int i = 1; i <= end; i++)
26.             {
27.                 count += count_1_in_a_num(i);
28.             }
29.             return count;
30.         }
33.     }