Using auto& ch in a range-based for loop allows iterating over each character directly without copying. The auto keyword infers the type, making the code cleaner.

When a continue statement is encountered inside a loop, it skips the remaining portion of the current iteration and jumps to the start of the next iteration. In a for loop, this means the loop's update statement (like i++ in for(int i=0; i<10; i++)) gets executed.

The short int type in C++ is typically 16 bits in size. Given that it's signed, half of the 2^16 possible values are negative. The range thus typically starts at -32768 and goes up to 32767.

In a loop, the break statement is used to exit the loop prematurely, halting its execution entirely. On the other hand, the continue statement skips the remaining part of the current iteration and jumps to the next iteration.

Class templates in C++ provide the ability to create classes that can work with a variety of data types without the need to redefine the class for each type, offering a level of genericity and flexibility in code design.

In C++, structs are typically used for lightweight user-defined data types. They default to public member access, making it easier to access the members directly without the need for getters and setters. Classes default to private access and are generally used when encapsulation is a primary concern.

The "Rule of Three" in C++ suggests that if a class requires a user-defined destructor, copy constructor, or assignment operator, it likely requires all three. This rule arises due to the intricacies of dynamic resource management (like memory allocation) in C++. Implementing or omitting one without the others can lead to unexpected behavior.

The diamond problem arises in C++ multiple inheritance when one class inherits from two classes that have a common base class. This can lead to ambiguity regarding which base class member should be accessed. The "virtual" keyword before the base class prevents the compiler from creating multiple instances of the base class, thus resolving the diamond problem.

Hierarchical Inheritance is when multiple derived classes inherit from a single base class. All the derived classes share the features of that one common base class. This kind of inheritance structure resembles a hierarchy or tree structure.

In C++, an abstract class is defined by having at least one pure virtual function. This means the function is declared but not defined within the class, ensuring that derived classes must implement it.