[Allegro] Visual C++, multiple definition, linker error

#include "main.hpp"

int main()
{
   
}
END_OF_MAIN();

#include "class.hpp"
using namespace std;

cObject::cObject() {
    string m_strName = "Object";
    int m_iPositionX = 0;
    int m_iPositionY = 0;
    BITMAP * m_bmImage = create_bitmap( 50, 50 );
    int m_iWidth = 50;
    int m_iHeight = 50;
}

cObject::cObject( string strName, int iPositionX, int iPositionY, string strPathOfFile ) {
    string m_strName = strName;
    int m_iPositionX = iPositionX;
    int m_iPositionY = iPositionY;
    BITMAP * m_bmImage = load_bmp( strPathOfFile.c_str(), default_palette );
    int m_iWidth = m_bmImage->w;
    int m_iHeight = m_bmImage->h;
}

#ifndef class_hpp
#define class_hpp
#include <string>
#include <allegro.h>

using namespace std;

class cObject {
public:
    string m_strName;
    int m_iPositionX;
    int m_iPositionY;
    BITMAP * m_bmImage;
    int m_iWidth;
    int m_iHeight;
    cObject();
    cObject( string, int, int, string );
};

class cCharacter
    : public cObject
{
public:
    int m_iHP;
    int m_iAttack;
    int m_iDefense;
    int m_iInjuryMin;
    int m_iInjuryMax;
    int m_iSpeed;
};

class cMonster
    : public cCharacter
{
};

class cPlayer
    : public cCharacter
{
};


#endif

D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x0 ) || In function ` ZN7cObjectC2Ev ':|
D:\p rojekty\inne\diablo\class.cpp | 4 | multiple definition of ` cObject::cObject() '|
D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x0 )
    : D:\p rojekty\inne\diablo\class.cpp | 4 | first defined here | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x346 ) || In function ` ZN7cObjectC1Ev ':| D:\p rojekty\inne\diablo\class.cpp | 4 | multiple definition of ` cObject::cObject() '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x346 )
    : D:\p rojekty\inne\diablo\class.cpp | 4 | first defined here | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x68c ) || In function ` ZN7cObjectC2ESsiiSs ':| D:\p rojekty\inne\diablo\class.cpp | 13 | multiple definition of ` cObject::cObject( std::string, int, int, std::string ) '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x68c )
    : D:\p rojekty\inne\diablo\class.cpp | 13 | first defined here | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x9aa ) || In function ` ZN7cObjectC1ESsiiSs ':| D:\p rojekty\inne\diablo\class.cpp | 13 | multiple definition of ` cObject::cObject( std::string, int, int, std::string ) '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x9aa )
    : D:\p rojekty\inne\diablo\class.cpp | 13 | first defined here | ||=== Build finished
    : 8 errors
    , 0 warnings ===|

D:\p rojekty\inne\diablo\class.cpp || In constructor ` cObject::cObject() ':|
D:\p rojekty\inne\diablo\class.cpp | 6 | warning
    : unused variable 'm_iPositionX' | D:\p rojekty\inne\diablo\class.cpp | 7 | warning
    : unused variable 'm_iPositionY' | D:\p rojekty\inne\diablo\class.cpp | 8 | warning
    : unused variable 'm_bmImage' | D:\p rojekty\inne\diablo\class.cpp | 9 | warning
    : unused variable 'm_iWidth' | D:\p rojekty\inne\diablo\class.cpp | 10 | warning
    : unused variable 'm_iHeight' | D:\p rojekty\inne\diablo\class.cpp || In constructor ` cObject::cObject( std::string, int, int, std::string ) ':| D:\p rojekty\inne\diablo\class.cpp | 15 | warning
    : unused variable 'm_iPositionX' | D:\p rojekty\inne\diablo\class.cpp | 16 | warning
    : unused variable 'm_iPositionY' | D:\p rojekty\inne\diablo\class.cpp | 18 | warning
    : unused variable 'm_iWidth' | D:\p rojekty\inne\diablo\class.cpp | 19 | warning
    : unused variable 'm_iHeight' | D:\p rojekty\inne\diablo\main.cpp || In function ` int _mangled_main() ':| D:\p rojekty\inne\diablo\main.cpp | 7 | warning
    : control reaches end of non - void function | D:\p rojekty\inne\diablo\class.cpp || In constructor ` cObject::cObject() ':| D:\p rojekty\inne\diablo\class.cpp | 6 | warning
    : unused variable 'm_iPositionX' | D:\p rojekty\inne\diablo\class.cpp | 7 | warning
    : unused variable 'm_iPositionY' | D:\p rojekty\inne\diablo\class.cpp | 8 | warning
    : unused variable 'm_bmImage' | D:\p rojekty\inne\diablo\class.cpp | 9 | warning
    : unused variable 'm_iWidth' | D:\p rojekty\inne\diablo\class.cpp | 10 | warning
    : unused variable 'm_iHeight' | D:\p rojekty\inne\diablo\class.cpp || In constructor ` cObject::cObject( std::string, int, int, std::string ) ':| D:\p rojekty\inne\diablo\class.cpp | 15 | warning
    : unused variable 'm_iPositionX' | D:\p rojekty\inne\diablo\class.cpp | 16 | warning
    : unused variable 'm_iPositionY' | D:\p rojekty\inne\diablo\class.cpp | 18 | warning
    : unused variable 'm_iWidth' | D:\p rojekty\inne\diablo\class.cpp | 19 | warning
    : unused variable 'm_iHeight' | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x0 ) || In function ` ZN7cObjectC2Ev ':| D:\p rojekty\inne\diablo\class.cpp | 4 | multiple definition of ` cObject::cObject() '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x0 )
    : D:\p rojekty\inne\diablo\class.cpp | 4 | first defined here | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x346 ) || In function ` ZN7cObjectC1Ev ':| D:\p rojekty\inne\diablo\class.cpp | 4 | multiple definition of ` cObject::cObject() '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x346 )
    : D:\p rojekty\inne\diablo\class.cpp | 4 | first defined here | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x68c ) || In function ` ZN7cObjectC2ESsiiSs ':| D:\p rojekty\inne\diablo\class.cpp | 13 | multiple definition of ` cObject::cObject( std::string, int, int, std::string ) '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x68c )
    : D:\p rojekty\inne\diablo\class.cpp | 13 | first defined here | D:\p rojekty\inne\diablo\.objs\class.o(.text + 0x9aa ) || In function ` ZN7cObjectC1ESsiiSs ':| D:\p rojekty\inne\diablo\class.cpp | 13 | multiple definition of ` cObject::cObject( std::string, int, int, std::string ) '| D:\p rojekty\inne\diablo\.objs\main.o(.text + 0x9aa )
    : D:\p rojekty\inne\diablo\class.cpp | 13 | first defined here | ||=== Build finished
    : 8 errors
    , 19 warnings ===|