Question

where is the calling of main function is done in c++??

Answer 1

Function declaration, is done to tell the compiler about the existence of the function. Function's return type, its name & parameter list is mentioned. Function body is written in its definition. Lets understand this with help of an example.

#include < iostream> using namespace std; int sum (int x, int y); //declaring function int main() { int a = 10; int b = 20; int c = sum (a, b); //calling function cout << c; } int sum (int x, int y) //defining function { return (X + y); }

Here, initially the function is declared, without body. Then inside main() function it is called, as the function returns sumation of two values, hence z is their to store the value of sum. Then, at last, function is defined, where the body of function is mentioned. We can also, declare & define the function together, but then it should be done before it is called.