In this section, we will learn how to write a simple C program. Let us know what hello world is in the c program; the line hello world program tells the compiler to display the statement “hello world “on screen.
How does the hello world program work?
Hello world program in c language
#include<stdio.h>
int main ()
{
Printf (“Hello world!”);
Return 0;
}
Now let us see how the program works.
The #include is a preprocessor command, and it tells the compiler to include the contents of stdio.h, that the is standard input and output file in the program and has functions such as printf () and scanf () to take input and output the display on the screen. Printf (), scanf () functions without writing #include<stdio.h> will not compile .printf is library function to send output on screen.
The execution of the program starts from the main () function.
The int written before the main () function is a return type of the main () function.
The curly braces { } just before the main function enclose the body of the main () function.
Return 0; statement is the exit status of the program; the program will end with this statement.
It is important to note that every statement in a C should end with a semicolon (;) if we miss adding any semicolon, it will be a compiler error.
How to write a C program on my computer?
All the C programs can be written and edited in text editors such as notepad, and they must be saved with a file name and with a .c extension.
Example: HelloWorld.c
Here HelloWorld is the file name.
If we not add .c extension, the compiler will not recognize it is a c program.
The different preprocessors in c programming language are
#include
#if
#define
#ifdef
#undef
Let us see how the comments can be added to a c program
To add single-line comments, we can use slash// followed by the comments
//*comments here*//
What is the stdio. h program in c language?
The studio stands for standard input and output and .h extensions of the file, including the header file.
The main use of this header file is that it helps to get the input from the keyboard and return the output on the screen.
Scanf () takes the input, and printf () prints the output on the screen.
FAQs
What is the “Hello World” program in C?
The “Hello World” program is a simple introductory program that is commonly used to illustrate the basic syntax of a programming language. In C, it typically consists of a few lines of code that display the phrase “Hello, World!” on the screen. This program demonstrates essential concepts such as including header files, defining the main function, and using the printf function for output.
How do you write a “Hello World” program in C?
Here is a basic example of a “Hello World” program in C:
c
#include <stdio.h>
int main() {
printf(“Hello, World!\n”);
return 0;
}
This program starts with including the stdio.h header file which is necessary for input and output functions. The main function is the entry point of any C program, and printf is used to output the text “Hello, World!” followed by a newline character \n.
Why do we use #include <stdio.h> in the “Hello World” program?
The #include <stdio.h> directive includes the Standard Input Output header file in the program, which contains declarations for input/output functions provided by the C standard library. This header is required for the printf function, which is used to display output on the console.
What is the purpose of return 0; at the end of the main function?
The statement return 0; in the main function signifies that the program has ended successfully. Returning 0 from the main function indicates a successful execution to the operating system. Other return values (usually non-zero) are typically used to indicate different types of errors.
Can the “Hello World” program be written differently in C?
Yes, the “Hello World” program can vary slightly depending on programming style or requirements. For instance, some variations might include comments to explain the code, use different types of output functions, or omit the return statement if the compiler defaults to returning zero. Here’s a slightly different version that includes a comment:
c
#include <stdio.h> // Include standard input/output header
// Main function executes the program
int main() {
printf(“Hello, World!\n”); // Display the message
return 0; // Return a success status code
}
These variations can help beginners understand different aspects of the C programming language.
