where is the main() function located in a c or c++ program
Entry point Alternatively, execution of a program can begin at a named point, either with a conventional name defined by the programming language or operating system, or at a caller-specified name. In many programming languages, notably C, this named point is a function called main; as a result, the entry point is often called the main function.
Function point Function points were defined in 1979 in Measuring Application Development Productivity by Allan Albrecht at IBM.[3] The functional user requirements of the software are identified and each one is categorized into one of five types: outputs, inquiries, inputs, internal files, and external interfaces. Once the function is identified and categorized into a type, it is then assessed for complexity and assigned a number of function points. Each of these functional user requirements maps to an end-user business function, such as a data entry for an Input or a user query for an Inquiry. This distinction is important because it tends to make the functions measured in function points map easily into user-oriented requirements, but it also tends to hide internal functions (e.g. algorithms), which also require resources to implement.