模块三：函数.docVIP

模块三：函数 Not before the attack must first observe, must be before the implementation of each policy to do it. When I started to attack, I want to be sure, there are more than one hundred percent capacity. In other words, even had the power to do one hundred, but I want to store enough force to attack only two hundred, instead of just to gamble. Module three: function The source of a C language consists of one or more functions It must have and can only have a primary function main () Program execution always starts with the main function It also ends the entire program because the main function ends The C function can only be nested Cannot define nested The C function calls itself at the time of definition This is the direct recursive fashion This part needs to clarify the following questions: (1) function definition: including function header and function body The function header also includes the function return value type, function name (formal parameter table) A function body is a series of statements enclosed by a pair of braces The formal parameter name of a function is irrelevant If the function does not need return value The return value type can be defined as void The return value of a function is determined by the value type returned by the first function The type of expression after return is inconsistent with it Automatic conversion The function can only return a value If a function needs to return multiple messages You should consider the formal arguments, with pointer arguments For example: int f (int a[]) Int n Int *max) returns the sum of the first n elements of the array a by the function The maximum value of the element is by setting the max pointer *max implementation in the body of the function External call time To use an address argument corresponding to the formal argument Max (2) function prototype: the function should be defined before it is called If a call precedes the definition You must make a prototype declaration of the previously define