Debugging system error! Need help

my projiect can't build, i don't understanding this problem, I think it about system
This is result of project debugging

1>------ Build started: Project: my, Configuration: Debug Win32 ------
1>Build started 9/13/2012 11:04:08 PM.
1>InitializeBuildStatus:
1> Touching "Debug\my.unsuccessfulbuild".
1>ClCompile:
1> List.cpp
1> Generating Code...
1> Compiling...
1> Stack.cpp
1> Queue.cpp
1> Poly.cpp
1> Generating Code...
1>ManifestResourceCompile:
1> All outputs are up-to-date.
1>Poly.obj : error LNK2005: "public: __thiscall List::List(void)" (??0List@@QAE@XZ) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::addFirst(int)" (?addFirst@List@@QAEXH@Z) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::clear(void)" (?clear@List@@QAEXXZ) already defined in List.obj
1>Poly.obj : error LNK2005: "public: __thiscall List::~List(void)" (??1List@@QAE@XZ) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::display(void)" (?display@List@@QAEXXZ) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::addConstant(int)" (?addConstant@List@@QAEXH@Z) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::addPoly(class List *)" (?addPoly@List@@QAEXPAV1@@Z) already defined in List.obj
1>Poly.obj : error LNK2005: "public: int __thiscall List::empty(void)" (?empty@List@@QAEHXZ) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::removeFirst(void)" (?removeFirst@List@@QAEXXZ) already defined in List.obj
1>Poly.obj : error LNK2005: "public: void __thiscall List::printPoly(void)" (?printPoly@List@@QAEXXZ) already defined in List.obj
1>c:\users\my\documents\visual studio 2010\Projects\my\Debug\my.exe : fatal error LNK1169: one or more multiply defined symbols found
1>
1>Build FAILED.
1>
1>Time Elapsed 00:00:02.48
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Those are link errors. They have nothing to do with the system or debugging.

It's telling you it's finding multiple definitions of some functions. You'll have to figure out why.

Quote:

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Originally Posted by Marin_Ngo

my projiect can't build, i don't understanding this problem, I think it about system
This is result of project debugging

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Read the errors carefully. It is telling you that you have two (or more) copies of the List implementation in your project.

Where is the constructor for List declared and defined? If it is in more than one module, then the linker is going to give you an error, and that is exactly what the problem is. You have the List constructor implemented in both List.cpp and Poly.cpp. You also have the entire List implementation implemented in both List.cpp and Poly.cpp. Why?

Regards,

Paul McKenzie