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How do I properly use the printf function?

+8 votes
asked Jan 4 by Kyden Busy (200 points) 1 flag
I've only used the cout and cin functions when I found out that calling functions using <iostream> doesn't really work, I started using printf. But I have no idea how to actually use it.

Please help, Kyden.

2 Answers

0 votes
answered Jan 7 by Peter Minarik (19,180 points)

iostream is C++ library. Maybe you compiled the code for C only (top right corner)?

The following code works fine in C++ (but obviously does not compile in C), check it:

#include <iostream>

int main()
    std::cout << "Hello World" << std::endl;
    return 0;
0 votes
answered Jan 7 by Pallabesh Maharana (450 points)

printf() function is a function of 'C' language. It is used to print something in output screen (Same as cout function in 'C++' language). This requires stdio.h header file to be executed (Some times it also runs without any header file, depending upon the compiler you use!).

 Syntax for displaying hello world :-


void main()


printf("hello world");


Note:- Make sure you give a semicolon(;) after printf statement.

And if you want to display value of a variable. 

Syntax to print value of a :-


void main()


int a=69;



Note:- Here %d is a format specifier. If you don't know, search for it...

commented Jan 7 by Pallabesh Maharana (450 points)
Hope you got it.
If not  then click here for more examples....
And if you don't know what is format specifier click here...
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