For some programs we don’t exactly know how many parameters will be used for a function. For situations like these we have to declare a variable length parameter list in function declaration. There is a way to inform the compiler that unknown number of arguments will be passed to the function. The method is to put three periods at the end in the function declaration. For Example:
int function(int i, int j, int k, …);
By this declaration compiler is informed that there will be three integer type parameters and unknown number of parameters after that. But we have to make sure that atleast one type of parameter is declared in the function declaration.