Collections exercise

collections.rs

// Given a list of integers, use a vector and return the mean (average), median (when sorted,
// the value in the middle position), and mode (the value that occurs most often; a hash map
// will be helpful here) of the list.
// Convert strings to Pig Latin, where the first consonant of each word is moved to the end
// of the word with an added “ay”, so “first” becomes “irst-fay”. Words that start with a
// vowel get “hay” added to the end instead (“apple” becomes “apple-hay”).
// Remember about UTF-8 encoding!

fn avg_and_median(v: &Vec<i32>) -> (i32, i32) {
    let mut copy = v.clone();
    let mut sum: i32 = 0;
    let len: usize = v.len();

    for i in v {
        sum += *i
    }
    // or sum = v.iter().fold(0, |acc, &x| acc + x);
    
    copy.sort();

    (sum / len as i32, copy[len / 2])
}

fn is_vowel(c: char) -> bool {
    match c {
        'a' | 'e' | 'i' | 'o' | 'u' => true,
        _                           => false
    }
}

fn piggify(s: &str) -> String {
    let mut r = String::new();
    let mut chars = s.chars();
    let first = s.chars().nth(0);

    match first {
        Some(c) if !is_vowel(c) => {
            chars.next();
            r.push_str(chars.as_str());
            r.push('-');
            r.push(c);
            r.push_str("ay");
        },
        Some(c) if is_vowel(c) => {
            r.push_str(chars.as_str());
            r.push('-');
            r.push_str("hay");
        }
        _                       => (),
    }

    r
}

fn main() {
    let vec = vec![6, 1, 5];
    let (avg, median) = avg_and_median(&vec);
    
    let strs = ["first", "apple", ""];
    
    println!("avg: {}, median: {}", avg, median);
    println!("first: {}, apple: {}, \"\": {}", piggify(strs[0]), piggify(strs[1]), piggify(strs[2]));
}