use std::collections::BTreeMap;
use std::ops::Bound::Included;

fn main () {
    test();
}

fn test() {
    let mut bt: BTreeMap<u128, u128> = BTreeMap::new();
    let mut a: u128 = 0;
    let div: u128 = 8;
    for x in 0..100_u128 {
        for y in 0..100_u128 {
            let zey = zeeify(x*div, y*div);
            a += 1;
            bt.insert(zey, a);
        }
    }

    let xs: u128 = 46;
    let ys: u128 = 46;
    let test: u128 = zeeify(xs, ys);
    let mut min: u128 = 1000000;
    let mut closest: (u128, u128) = (0,0);
    for r in 0..div {
        let yss = (ys-div/2) + r;
        let xss = xs-div/2;
        let minzee = zeeify(xss, yss);
        let maxzee = zeeify(xss+div, yss);
        for v in bt.range( (Included(minzee), Included(maxzee)) ) {
            println!("{:?}", v);
            if min > abs_u128(*v.0, test) {
                min = abs_u128(*v.0, test);
                closest.0 = *v.0;
                closest.1 = *v.1;
            }
        }
    }
    println!("{:?} {:?} {:?}", min, closest, test);
}

fn abs_u128(a: u128, b: u128) -> u128 {
    if a > b {a - b} else { b-a }
}

fn zee_neighbors(zee: u128, div: u128) -> [u128; 4] {
    let a: u128 = 0b10101010101010101010101010101010;
    let b: u128 = 0b01010101010101010101010101010101;
    let t: u128 = (((zee & a) - div) & a) | (zee & b);
    let b: u128 = (((zee & b) + div) & a) | (zee & b);
    let l: u128 = (((zee & b) - div) & b) | (zee & a);
    let r: u128 = (((zee & a) + div) & b) | (zee & a);
    [t,b,l,r]
}

fn zeeify(a: u128, b: u128) -> u128 {
    let mut f: u128 = 0;
    for i in 0..16 {
        f |= ((a & 1<<i) << i) | ((b & 1<<i) << (i+1));
        //println!("{:b} {:b} | {:b} {:b} | {:b}", a, a&1<<i, b, b&1<<i, f);
    }
    f
}