What is the purpose of atomic in C++?

In C++, the atomic class is used to ensure the atomicity of operations, which means that in a multi-threaded environment, an operation will either fully complete or not execute at all, with no in-between state.

The atomic class can be used to access and modify shared data atomically in order to avoid data race and inconsistency between different threads. It provides methods to perform atomic operations such as load, store, exchange, addition, subtraction, logical AND, and logical OR.

Using atomic classes ensures that operations on shared data in a multi-threaded environment will not lead to incorrect modifications or inconsistent states, which is crucial for writing thread-safe concurrent code.