Solution: The forward_list uses singly linked list hence it is uni-directional. In the forward_list, the container provides insertion and removal at anywhere in the program.

Solution: In vectors, by size we mean the number of elements in that vector array.

Solution: The vector maintains a certain order of its elements, so that when a new element is inserted at the beginning or in the middle of the vector, Subsequent elements are moved backwards in terms of their assignment operator or copy constructor.

Solution: Adapters are data types from STL that adapt a container to provide specific interface.

Solution: Associated iterator type is used to iterate over container.

Solution: Function objects are objects specifically designed to be used with a syntax similar to that of functions.

Solution: A function object can contain state. The second is that a function object is a type and therefore can be used as a template parameter.

Solution:  header is need to be used with function objects.

Solution: Function objects are instances of a class with member function operator() defined. This member function allows the object to be used with the same syntax as a regular function call.

Solution: In the case of binary function objects, this operator() member function will take two parameters.