What does "undefined reference to 'PrintList'" or "undefined reference to 'InsertAtRoot'" mean after compiling in the C programming language? Thanks.

This occurs when the function declaration and the function definition do not match. As the function, the prototype can be PrintList(D*) and the function definition might have been listed like void PrintList(). And this is the reason why the declaration and the definition are not matching. The same thing must have occurred with the InsertAtRoot, and in all such cases, this error message is being shown after the compilation of the C program in the C programming language.

Explanation:

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