Table of content

What is this :grey_question:

The rules of the game are explained in my original post.

37th Challenge

Challenge

Today I’m solving today’s AoC day 7 2021.

Solution :white_check_mark:

This challenge was fun, more brute force friendly than yesterdays challenge.

	fn main() {

	    let mut v =INPUT.split(",")
	        .map(|x| x.parse::<i32>().unwrap())
	        .collect::<Vec<i32>>();

	    v.sort();

	    let c = v.len();

	    let median = match c%2 {
	        1 => *v.get(c/2).unwrap() as f32,
	        _ => ((v.get(c/2-1).unwrap()+v.get(c/2).unwrap()) as f32).abs() / 2f32
	    };

	    println!("sol1:{}",v.iter().fold(0,|acc,inst|{acc+(*inst-(median as i32)).abs()}));

	    let x = (0..*(v.get(v.len()-1).unwrap()))
	        .fold(i32::MAX,|acc, k|
	            {(v.iter()
	                .fold(0,|acc,inst|acc+find_fuel2((*inst-k).abs()))
	            ).min(acc)
	            }
	        );

	    println!("sol2:{}",x);
	}

	fn find_fuel2(x: i32) -> i32{
	     x*(x+1)/2
	}

	const INPUT:&str = "16,1,2,0,4,2,7,1,2,14";

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