求欧拉常数的提问解决方案

求欧拉常数的提问
下面是求欧拉常数的C++的代码：
[code=C/C++][/code]#include<iostream>
#include<cmath>
int main(int char* [])
{
double result=0;
for(unsigned long int i=1;i<=500000;++i)
result+=1./i-std::log((i+1.)/i);
cout<<"gamma="<<result<<endl;
return 0;
}
但是编译会出现错误：error C2039: 'log' : is not a member of 'std'
为啥会这样？c++的标准库改变了吗？
大家帮忙解答解答，谢谢！

[解决办法]

C/C++ code

#include<iostream>#include<cmath>using std::cout;using std::endl;int main(int argc, char **argv){    double result=0;    for(unsigned long int i=1;i<=500000;++i)        result+=1./i-std::log((i+1.)/i);    cout<<"gamma="<<result<<endl;    return 0;}
[解决办法]
C/C++ code
代码放在这的
[解决办法]
探讨


C/C++ code

#include<iostream>
#include<cmath>

using std::cout;
using std::endl;

int main(int argc, char **argv)
{
    double result=0;
    for(unsigned long int i=1;i<=500000;++i)
        result+……