1 Console.Write("请输入整数 n:");
2 string strN = Console.ReadLine();
3
4 Console.Write("请输入整数 k:");
5 string strK = Console.ReadLine();
6
7 int n = 0;
8 int k = 0;
9 if (!int.TryParse(strN, out n) || !int.TryParse(strK, out k))
10 {
11 Console.Write("请输入整数!");
12 return;
13 }
14
15 if (k <= 0)
16 {
17 Console.Write("k 必须为正整数!");
18 }
19
20 double j = 1, r = 0;
21
22 while ((r + j) * (r + j) <= n)
23 {
24 r += j;
25 }
26
27 if (r * r == n)
28 {
29 Console.Write(r);
30 return;
31 }
32
33 for (int i = 0; i < k ; i++)
34 {
35 j /= 10;
36 while ((r + j) * (r + j) < n)
37 {
38 r += j;
39 }
40 }
41
42 Console.WriteLine(r);
43
44 Console.WriteLine(r.ToString().Last());
