41 lines
2.1 KiB
Markdown
41 lines
2.1 KiB
Markdown
---
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title: Hello World C
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---
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## Hello World
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Probably the first line of text that everyone prints out on the console when one begins his/her remarkable journey of this endless programming world.
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To write on console you can use the function `printf()` contained in the library `include <stdio.h>`
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```C
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#include <stdio.h>
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/* Any text in between these two characters is a block comment.
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Block comments, unlike inline comments, can span multiple lines.
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Comments are ignored by the compiler and will not be executed.
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*/
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int main(void)
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{
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printf("Hello, World\n"); // text after two slashes '/' are called inline comments.
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return 0;
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}
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```
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## Explanation
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* The `#include <stdio.h>` is a preprocessor directive. This directive tells preprocessor to include the contents of `stdio.h` (standard input and output) file in this file.
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* The `stdio.h` file contains functions such as `scanf()` and `printf()` to take input and display output respectively.
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* If you use `printf()` function without writing `#include <stdio.h>`, the compiler will generate an error during compliation of the program.
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* The execution of a C program starts from the `main()` function. We write `int` before it to specify that the program returns a integer value.
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* The `printf()` is a library function to send formatted output to the standard output stream, most commoly the screen. In this program, the `printf()` displays `Hello, World!` text on the screen.
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* `\n` is used here to take the cursor to the next line. Hence, if we print anything after this command, it will be printed on a new line.
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* The `return 0;` statement is the "Exit code" of the program. In simple terms, the program ends with this statement or it signifies that function does not return any value.
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## Output:
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```
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Hello, World!
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```
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#### More Information
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* Conventionally, the first ever program you write is the "hello world" program, be it in any language.
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* This is because Brian Kernighan was the first to write "hello, world" program for the documentation of the BCPL programming language developed by Martin Richards. |