Pow(x,n)

 1 class Solution {
 2 public:
 3     double pow(double x, int n) {
 4         // Start typing your C/C++ solution below
 5         // DO NOT write int main() function
 6         if(n==0)
 7             return 1;
 8         if(x==0)
 9             return 0;
10         if(x==1)
11             return 1;
12         if(x==-1)
13             return n%2?-1:1;
14         if(n<0)
15         {
16             n=-n;
17             int i;
18             double d=1;
19             for(i=0;i<n;i++)
20             {
21                 d=d/x;
22             }
23             return d;
24         }
25         if(n>0)
26         {
27             int i;
28             double d=1;
29             for(i=0;i<n;i++)
30             {
31                 d*=x;
32                 if(d==0) 
33                     return 0;
34             }
35             return d;
36         }
37     }
38 };
原文地址:https://www.cnblogs.com/mengqingzhong/p/3073208.html