In C++, the try block is used to wrap the code that might throw an exception. If any part of the code inside the try block throws an exception, the execution immediately shifts to the corresponding catch block to handle the exception, if a matching catch exists.

When a recursive algorithm recalculates the same values repeatedly, it leads to unnecessary computational overhead. Memoization is a technique where you store the results of expensive function calls and return the cached result when the same inputs occur again, preventing redundant calculations. This is especially useful in recursive algorithms like those seen in dynamic programming.

The ASCII value for the uppercase letter 'A' is 65 in decimal. ASCII (American Standard Code for Information Interchange) assigns each character a unique number between 0 and 127.

The break statement is primarily used to terminate loops and switch statements. Using a break outside these constructs, like directly inside a function without a loop or switch, would result in a compilation error as it wouldn't have a clear context to operate within.

The goto statement in C++ provides an unconditional jump from the goto to a labeled statement found elsewhere in the code. Although it allows for more flexibility in controlling the flow, its overuse or misuse can make the code less readable and more prone to errors. The modern programming paradigm usually discourages its use.

In C++, most of the operators can be overloaded with a few exceptions. Among the operators that cannot be overloaded are: the scope resolution operator ::, the member selection operators . and .*, and the ternary conditional operator ?:.

In C++, to declare a function that returns an integer, the correct syntax is "int functionName()". The type "int" signifies that the function's return type is an integer, and the parentheses "()" indicate it's a function declaration. Actual implementation or body of the function would follow the declaration.

In C++11's range-based for loop, the const keyword ensures that elements are not modified, effectively preventing unintentional copies or modifications to the elements.

The loop while(true) will continue to execute indefinitely since the condition is always true. This can potentially lead to an infinite loop, consuming CPU resources, and making the program unresponsive unless externally interrupted.

When a class is frequently copied or assigned, it's crucial to consider the efficiency of these operations. Move semantics, introduced in C++11, allow resources to be "moved" from one object to another, without making a copy. This can greatly improve performance. Shallow copy can lead to issues like double deletion, and avoiding constructors or only using private members doesn't address the efficiency of copying or assignment.