1 #include "stdafx.h" 2 #include 
     
       3 #include 
      
        4 #include 
       
         5 /* 6     题目:实现函数 doublePower(double base,int exponenet), 7     求base的exponenet次方,不得使用库函数，同时不需要考虑大数问题 8 */ 9 using namespace std;10 bool g_InvalidInput = false;11 bool equal(double num1,double num2)12 {13     if((num1 - num2 >-0.0000001)&&(num1-num2<0.0000001))14     {15         return true;16     }17     else return false;18 }19 double PowerWithUnsignedExponenet(double base,unsigned int exponent)20 {21     double result = 1.0;22     for(unsigned int i = 1;i<=exponent;++i)23     {24         result*= base;25     }26     return result;27 }28 double Power(double base,int exponent)29 {30     g_InvalidInput = false;31     if(equal(base,0.0)&&exponent<0)32     {33         g_InvalidInput = true;34         return 0.0;35     }36 37     unsigned int absExponent = (unsigned int) (exponent);38     if(exponent<0)39         absExponent = (unsigned int)(-exponent);40     double result = PowerWithUnsignedExponenet(base,absExponent);41     if(exponent <0)42         result = 1.0/result;43     return result;44 }45 46 int _tmain(int argc, _TCHAR* argv[])47 { 48     cout<
        
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