Rust learning: lessons, notes, and exercise crates

learn-challenges/.gitignore

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+/target

learn-challenges/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "learn-challenges"
+version = "0.1.0"

learn-challenges/Cargo.toml

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+[package]
+name = "learn-challenges"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

learn-challenges/src/main.rs

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+use std::{collections::HashMap, vec};
+
+fn main() {
+    let list = vec![3, 1, 4, 1, 5];
+
+    let med: usize = list.len() / 2;
+
+    println!("this is the median {}", list.get(med).unwrap_or(&0));
+
+    let mut count = HashMap::new();
+
+    for &v in &list {
+        let x = count.entry(v).or_insert(0);
+        *x += 1;
+    }
+
+    let mut mode = 0;
+    let mut max_count = 0;
+
+    for (k, v) in &count {
+        if *v > max_count {
+            max_count = *v;
+            mode = *k;
+        }
+    }
+
+    println!("this is the mode {}", mode);
+
+    let latin = "apple banana".to_string();
+
+    println!("{latin} = this is the pig latin: {}", pig_latin(&latin));
+
+    let latin = "kdlkjlkdsgjh gkjldgjd".to_string();
+
+    println!("{latin} = this is the pig latin: {}", pig_latin(&latin));
+}
+
+fn pig_latin(s: &String) -> String {
+    let mut results_words: Vec<String> = Vec::new();
+
+    for word in s.split_whitespace() {
+        let mut vowel_idx = None;
+        for (i, v) in word.char_indices() {
+            match v {
+                'a' | 'i' | 'e' | 'u' | 'o' => {
+                    vowel_idx = Some(i);
+                    break;
+                }
+                _ => {}
+            }
+        }
+
+        let transformed = match vowel_idx {
+            Some(0) => format!("{}-hay", word),
+            Some(idx) => {
+                let x = &word[..idx];
+                let rmdr = &word[idx..];
+                format!("{rmdr}-{x}ay")
+            }
+            None => word.to_string(),
+        };
+        results_words.push(transformed);
+    }
+
+    results_words.join(" ")
+}