46 lines
1.9 KiB
Markdown
46 lines
1.9 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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int main(void)
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{
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printf("hello, world\n"); // lines starting with this (//) are called comments..
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//this code prints "Hello World!"
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printf("Hello World!\n"); //<-- the \n character prints a newline after the string
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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 command. This command tells compiler to include the contents of `stdio.h` (standard input and output) file in the program.
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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 program will not be compiled.
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* Two backslash characters (//) are used to _comment_ the code, for better understandability. Anything after // on a line is ignored while compiling the program.
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* The execution of a C program starts from the `main()` function.
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* The `printf()` is a library function to send formatted output to the screen. In this program, the `printf()` displays `Hello World!` text on the screen.
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* The `\n` in `printf` creates a new line for the forthcoming text.
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* The `return 0;` statement is the "Exit status" of the program. In simple terms, program ends with this statement
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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.
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