Basic Program Construction

//first.cpp

#include <iostream>

#include <stdlib.h>

using namespace std;

int main(){

cout<< "Welcome to this course\n";

system("PAUSE");

return 0;

}

Explanation:

This program consists of a single function called main().
Because of the parentheses()the compiler comes to know that this a function not a variable.
The parentheses aren’t always empty. They’re used to hold function arguments (values passed from the calling program to the function).
Line number 2 and 3 are not part of the function.
The word int preceding the function name indicates that this particular function has a return value of type int.
The bodyof a function is surrounded by braces (sometimes called curly brackets).
Every function must use this pair of braces around the function body.
A function body can consist of many statements but this function has only three statements (line number 5, 6 and 7)
You can put several statements on one line and one statement in over two or more lines.

cout<<"Welcome to this course\n";

cout <<"Welcome Students\n" ; return 0;

We don’t recommend these syntax. it’s nonstandard and hard to read. but it does compile correctly.
#include is a preprocessor directive, which must be written on one line.
#include <iostream> tells the compiler to first include standard C++ library named iostream to our project.
A string constant "Welcome to this course\n" can also be broken into separate lines if u insert a backslash (\) at the line break or divide the string into two separate strings, each surrounded by quotes.

cout

<<"Welcome "

"to this "

"course\n"

;

cout

<<"Welcome \

to this \

course\n"

;

A programs may consists of many functions but the main() function will be executed first.
If there is no function called main()in your program, an error will be reported when you run the program.
main()function may also call other functions.

New Proggrams