The "do-while" loop in C++ always executes its body once before checking the condition. So even if the condition in the "while" part is "false", the body of the loop will execute once. This differentiates it from the "while" loop which checks the condition before the first execution.

The switch-case structure in C++ is best suited for scenarios where a single variable's value needs to be checked against a series of constants, often seen with enumerated values. It's a cleaner and more readable alternative to a long series of if-else statements in such cases.

Function call overhead is the extra time and resources needed when a function is called. Using inline functions can help reduce this overhead, especially in recursive algorithms, because the function's code gets inserted (or "inlined") at each point where the function is called, eliminating the need for the typical call and return process, which can be resource-intensive.

In C++, the modulo operator % is used to determine the remainder of a division operation between two numbers. For example, 7 % 3 would yield a result of 1, as when 7 is divided by 3, the remainder is 1. It's a very useful operator, especially in situations that require calculations around loops and array indices.

When passing arguments by reference in C++, any modifications made to the parameter within the function directly alter the original argument. This is different from passing by value, where the function works on a copy and the original remains unchanged.

To execute a loop for a specific number of times using an iterator, a common approach is to use a for loop. You initialize the iterator before the loop starts, use the loop's condition to check against the container's end iterator, and increment the iterator within the loop's iteration expression.

When working with binary files in C++, the ios::binary mode is often paired with another mode to specify the operation, such as ios::out for writing or ios::in for reading. This ensures that the file is treated as a binary file.

Direct recursion occurs when a function calls itself directly, whereas indirect recursion involves a function calling another function that eventually calls the original function. It's a cycle of calling between two or more functions.

In a for loop, if the condition is omitted, it's treated as always true. Therefore, the loop will execute indefinitely unless there's a break statement or some external factor that interrupts its execution.

In a switch-case structure in C++, the conditions or cases must be of an integer or enumeration type. Floating-point and boolean values cannot be used as cases.