In recursion, the call stack is a critical component that keeps track of function calls and their corresponding local variables and parameters. Whenever a function is called, its information is pushed onto the call stack, including the return address (the location in code where the function call should return after completion) and the values of local variables and parameters.
In the context of recursion in C++, each recursive function call creates a new activation record (also known as a stack frame) on top of the call stack. This record stores the necessary information for that specific invocation of the function. The call stack follows a Last-In-First-Out (LIFO) order, meaning that the most recent function call is at the top of the stack.
As the recursive function calls itself, the call stack grows with each new invocation. This stack expansion continues until a base case is reached, which signifies the termination of recursion. At this point, the function calls start returning one by one, and the corresponding stack frames are popped off the call stack.
It's important to manage the call stack properly during recursion to prevent stack overflow errors, which occur when the call stack exceeds its maximum capacity. This can happen if recursion is not properly controlled or if the base case is not defined correctly.
