Compiler errors

[EUjwb7Xj]

I'm fairly new to C++, and I'm having problems when compiling this program, any help with any of the error would be appreciated
Error list:
operator.h(9): error C2011: 'Operator' : 'class' type redefinition
operator.h(9) : see declaration of 'Operator'
operator.cpp(11): error C2027: use of undefined type 'Operator'
operator.h(9) : see declaration of 'Operator'
operator.cpp(11): error C2146: syntax error : missing ')' before identifier 'filename'
operator.cpp(11): error C2146: syntax error : missing ';' before identifier 'filename'
operator.cpp(11): error C2079: 'string' uses undefined class 'Operator'
operator.cpp(11): error C2059: syntax error : ')'
operator.cpp(12): error C2470: 'filename' : looks like a function definition, but there is no parameter list; skipping apparent body
operator.cpp(20): error C2027: use of undefined type 'Operator'
\operator.h(9) : see declaration of 'Operator'
operator.cpp(24): error C2065: 'Frequency' : undeclared identifier
operator.cpp(25): error C3312: no callable 'begin' function found for type ''unknown-type''
operator.cpp(25): error C3312: no callable 'end' function found for type ''unknown-type''
main.cpp(8): error C2079: 'myOperatorObject' uses undefined class 'Operator'
main.cpp(8): error C2440: 'initializing' : cannot convert from 'const char [15]' to 'int'
1> There is no context in which this conversion is possible
main.cpp(10): error C2228: left of '.getCharFrequency' must have class/struct/union
1> type is 'int'

Operator.cpp

  #include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>
#include <map>
#include <cstddef>
//using namespace std;

#include "Operator.h"

Operator::Operator(string filename)
{               
    ifstream infile; 
    int i = 0;                              
    infile.open(filename.c_str());        
    getline(infile,Frequency);            
    infile.close(); 
}

std::map<char, std::size_t> Operator::getCharFrequency()
{
	int c;
    std::map<char, std::size_t> freq;
    for(auto c: Frequency)
    {
        if( freq.find(c) == freq.end())
            freq[c] = 1; 
        else
            ++freq[c];
    }
    return freq;
}

Operator.h

#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>
#include <map>
#include <cstddef>
using namespace std;
// Define class:
class Operator {
public:
    //Constructor    
    Operator(string filename);
    //a function that does the job
    std::map<char, std::size_t> getCharFrequency();
private:
    //private variable the class is working with
    string Frequency;
};

main.cpp

#include "stdafx.h"
#include "Operator.h"
#include "Operator.cpp"

int main()
{
//instatntiate an "Operator" by calling the Constructor
    Operator myOperatorObject("richardiii.txt");
    //use the function to get the Char-Frequency Map
    std::map<char, std::size_t> freq = myOperatorObject.getCharFrequency();
    //do whatever you want with it
    for(auto elem: freq)
        std::cout << elem.first << " -> " << elem.second << std::endl;
}

Thanks in advance

[jlb]

You shouldn't be #including the implementation file (.cpp) you should be adding that file to your project.

Also your include file should have include guards.