Could I create my own library to include in programs?

I was wondering if I can assemble and compiler a code library of the most used functions I use. For example I am currently trying to develop a low-level digital logic circuit simulator and I have created the code for the logical gates AND, OR, NOT, XOR...Instead of including their prototypes and code each time, how could I just write let's say #include <loggates.h> and have them ready?
Thanks in advance!

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Code:

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func.h.....

int func1();
int func2();
int func3();

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Code:

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func.cpp

#include "func.h"

int func1()
{
// impl
}

int func2()
{
//impl
}

int func3()
{
//impl
}

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Code:

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main.cpp

#include "func.h"
int main()
{
int a=func1();
int b=func2();
int c=func3();
return 0;
}

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