How to avoid compilation errors with multiple header files in C++?

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SUMMARY

The discussion addresses compilation errors in C++ caused by including multiple header files, specifically when using Stack.h and Activity.h together. The error arises from Activity.h being defined multiple times. Solutions include using the `#pragma once` directive or the traditional include guard method with `#ifndef`. Implementing these strategies effectively prevents redefinition errors during compilation.

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Sam Groves
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I have a class Stack with a header file Stack.h which uses up another class with a header file Activity.h

I have a third class ActivityManager which uses up both the Stack and the Activity class.If I run the program and add in both Activity.h and Stack.h to the #include list I get a compilation error:Activity.h is defined 2 times in the script.How do I solve this issue?
 
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You can use the pragma once idiom or some of the other methods shown on that page.
 
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From a C standpoint, I would use #ifndef <Some variable defined in the header you are trying to include>.
 

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