VC++中 error LNK2019问题
描述：我编了个简单的计算器程序，如下

#include "stdafx.h"
#include "Cal.h"
#include "CalDlg.h"
#include "afxdialogex.h"
#include<cmath>



void CCalDlg::OnBnClickedNumber1()
{
show[m_Point]='1';
m_String =m_String+'1';
UpdateData(FALSE);
m_select=Charge(show,m_Point);
if(m_select==0)
{
m_Number1=m_Number1*10+1;
}
else
{
m_Number2=m_Number2*10+1;
}
m_Point++;


}
int Charge(char show[] ,int point)
{
int k= point;
while(k>=0)
{
if((show[k]=='+')|(show[k]=='-')|(show[k]=='*')|(show[k]=='/'))
return k;
else
return 0;
k++;
}

}




错误提示：
error LNK2019: unresolved external symbol "public: int __thiscall CCalDlg::Charge(char * const,int)" (?Charge@CCalDlg@@QAEHQADH@Z) referenced in function "public: void __thiscall CCalDlg::OnBnClickedNumber1(void)" (?OnBnClickedNumber1@CCalDlg@@QAEXXZ)





不知道缺少什么库？烦请大牛指点！谢谢

[解决办法]
试试 m_select=::Charge(show,m_Point);
[解决办法]
int CCalDlg::Charge(char show[] ,int point)
[解决办法]