Table of content

Table of content
- What is this
- 81st Challenge
  - Challenge
  - Solution

What is this

The rules of the game are explained in my original.

81st Challenge

Challenge

Like every year, I am going to participate in the Advent of Code. Lets get started with advent of code

Solution

fn main() {
    let input = include_str!("input.txt");
    let numbers = input.split_whitespace();

    let mut left = numbers
        .clone() 
        .enumerate()
        .filter(|(i, _)| i % 2 == 0)
        .map(|(_, n)| n.parse::<i32>().unwrap())
        .collect::<Vec<i32>>();

    let mut numbers = input.split_whitespace(); 
    let mut right = numbers
        .enumerate()
        .filter(|(i, _)| i % 2 == 1)
        .map(|(_, n)| n.parse::<i32>().unwrap())
        .collect::<Vec<i32>>();

    left.sort();
    right.sort();

    let result = left
        .iter()
        .zip(right.iter())
        .map(|(l, r)| (l - r).abs())
        .sum::<i32>();

    let result2: usize = left
        .iter()
        .map(|&l| (l as usize)*right.iter().filter(|&&x| x == l).count())
        .sum();

    println!("Result1: {}", result);
    println!("Result2: {}", result2);
}