fin

src/main.rs

@@ -1,3 +1,101 @@
+use rand::RngExt;
+use rand_distr::Binomial;
+use std::env;
+use std::io;
+
 fn main() {
-    println!("Hello, world!");
+    let args = env::args().skip(1).collect::<Vec<String>>();
+    let options = Options::from_args(&args);
+    guess(&options)
+}
+
+struct Options {
+    min: u32,
+    max: u32,
+    use_normal: bool,
+}
+
+impl Options {
+    fn parse(&mut self, args: &Vec<String>) {
+        let mut args = args.iter();
+        while let Some(arg) = args.next() {
+            match arg.as_str() {
+                "--normal" => self.use_normal = true,
+                "--max" | "-m" => {
+                    let max_value = args
+                        .next()
+                        .expect("Number proceeding --max should be a number");
+                    self.max = max_value
+                        .trim()
+                        .parse()
+                        .expect("Number proceeding --max should be a number");
+                }
+                "--min" => {
+                    let min_value = args
+                        .next()
+                        .expect("Number proceeding --min should be a number");
+                    self.min = min_value
+                        .trim()
+                        .parse()
+                        .expect("Number proceeding --min should be a number");
+                }
+                _ => panic!("Unrecognized argument {:?}", arg),
+            }
+        }
+        if self.max < self.min {
+            panic!("min > max, wtf are you even talking about?");
+        }
+    }
+
+    fn from_args(args: &Vec<String>) -> Options {
+        let mut opts = Options::new();
+        opts.parse(args);
+        opts
+    }
+
+    fn new() -> Options {
+        Options {
+            use_normal: false,
+            min: 0,
+            max: 10,
+        }
+    }
+}
+
+fn random_uniform_range(min: u32, max: u32) -> u32 {
+    let diff = max - min;
+    (rand::random::<u32>() % diff) + min
+}
+
+fn random_binomial_range(min: u32, max: u32) -> u32 {
+    let diff = max - min;
+    let bin = Binomial::new(diff as u64, 0.5).expect("Could not make range");
+    rand::rng().sample(bin) as u32 + min
+}
+
+fn guess(opts: &Options) {
+    let to_guess: u32 = match opts.use_normal {
+        true => random_binomial_range(opts.min, opts.max),
+        false => random_uniform_range(opts.min, opts.max),
+    };
+
+    let mut input_string = String::new();
+    println!(
+        "Enter a number in the range {}<=guess<{}",
+        opts.min, opts.max
+    );
+    io::stdin()
+        .read_line(&mut input_string)
+        .expect("Could not read string");
+
+    let input_number = input_string
+        .trim()
+        .parse::<u32>()
+        .expect("Could not parse input");
+
+    if input_number == to_guess {
+        println!("You got it right!");
+    } else {
+        println!("The correct number was {}!", to_guess);
+    }
 }