Modified README.md

README.md

@@ -1 +1,56 @@
-# pm-checker
+# pn-checker (Prime Number Checker)
+
+pn-checker is a slightly silly and useless command line tool.
+It checks whether the number specified is a prime number or not.
+And sometimes, pn-checker playfully returns you "Think for yourself, stupid!".
+
+## Installation
+
+```shell
+> go install github.com/gracefulm/pn-checker@latest
+```
+
+## Usage
+
+```shell
+> pn-checker -h
+pn-checker checks whether the number specified is a prime number or not.
+And sometimes, it says "Think for yourself, stupid!" to you.
+
+Usage:
+  pn-checker [flags] [arg(positive integer)]
+
+Examples:
+  pn-checker 997
+
+Flags:
+  -d, --diligent   seriously check if it's a prime number
+  -h, --help       help for pn-checker
+  -v, --version    version for pn-checker
+```
+
+## Example
+
+```text
+> pn-checker 13
+Congrats!! The number 13 is a prime number.
+```
+
+OR
+
+```text
+> pn-checker 13
+
+ _____ _     _       _       __
+|_   _| |__ (_)_ __ | | __  / _| ___  _ __
+  | | | '_ \| | '_ \| |/ / | |_ / _ \| '__|
+  | | | | | | | | | |   <  |  _| (_) | |
+  |_| |_| |_|_|_| |_|_|\_\ |_|  \___/|_|
+                                 _  __        _               _     _   _
+ _   _  ___  _   _ _ __ ___  ___| |/ _|   ___| |_ _   _ _ __ (_) __| | | |
+| | | |/ _ \| | | | '__/ __|/ _ \ | |_   / __| __| | | | '_ \| |/ _  | | |
+| |_| | (_) | |_| | |  \__ \  __/ |  _|  \__ \ |_| |_| | |_) | | (_| | |_|
+ \__, |\___/ \__,_|_|  |___/\___|_|_|( ) |___/\__|\__,_| .__/|_|\__,_| (_)
+ |___/                               |/                |_|
+
+```