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C++ Classes

Group data and behavior.

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The concept

A class defines a custom type. Public members are accessible to users of that type.

Code example

C++

#include <iostream>
class Counter { public: int value = 0; void increment() { value++; } };
int main() { Counter c; c.increment(); std::cout << c.value; }

Output

Example details

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1#include <iostream>

2class Counter { public: int value = 0; void increment() { value++; } };

3int main() { Counter c; c.increment(); std::cout << c.value; }

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Start to inspect the source, values, and output. These prepared steps explain the published sample; grouped loop steps describe multiple iterations.

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Prepared trace of the published program. Some rows group repeated iterations.
Step / line	What happens	State after step	Output so far
	Define Counter with an integer value and increment method.	`—`	—
	Create c with value 0, call increment, then print value.	`c.value = 1`	1

Behind the scenes

How C++ processes this code

The C++ compiler produces a native executable. Execution enters main, where objects and function calls perform the work.