C++ Regarding .h and .cpp - Multiple definition of
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I face a error of "multiple definition of "
I got 3 files, namely currency.h, currency.cpp,main.cpp

At currencyConverter.h under currencyConverter class 
I did

    public:
       void getInbetween(string,string,string,string);

Then at currencyConverter.cpp I did

    void currencyConverter::getInbetween(string selection,string str2,string str3,string sdata)
    {
    //codes..
    }

But i receive this error

    currencyConverter.o: In function `currencyConverter::getInbetween(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >)':
    currencyConverter.cpp:(.text+0x0): multiple definition of `currencyConverter::getInbetween(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >)'

How to get this fix.. I did not use it twice.
