use std::{fs::read_to_string, io::Result};

fn all_diff<T: PartialEq>(list: &[T]) -> bool {
    for i in 0..list.len() {
        let a = &list[i];
        for j in 0..i {
            let b = &list[j];
            if a == b {
                return false;
            }
        }
    }
    true
}

fn main() -> Result<()> {
    let mut p1_ring_buf = [None; 4];
    let mut p1_pos = 0;
    let mut p2_ring_buf = [None; 14];
    let mut p2_pos = 0;

    let mut p1_result = 0;
    let mut p2_result = 0;

    for (i, c) in read_to_string("input.txt")?.chars().enumerate() {
        p1_ring_buf[p1_pos] = Some(c);
        p1_pos += 1;
        if p1_pos == p1_ring_buf.len() {
            p1_pos = 0
        }

        p2_ring_buf[p2_pos] = Some(c);
        p2_pos += 1;
        if p2_pos == p2_ring_buf.len() {
            p2_pos = 0
        }

        if p1_result == 0 {
            if i >= p1_ring_buf.len() && all_diff(&p1_ring_buf) {
                p1_result = i + 1;
            }
        }

        if p2_result == 0 {
            if i >= p2_ring_buf.len() && all_diff(&p2_ring_buf) {
                p2_result = i + 1;
            }
        }
    }

    println!("Part 1: {}", p1_result);
    println!("Part 2: {}", p2_result);

    Ok(())
}