Code shared from the Rust Playground

playground.rs

fn steps(mut a: i128, mut b: i128, mut c: i128, mut d: i128) -> u32 {
    let mut i = 0;
    while coeffs != (0, 0, 0, 0) {
        (a, b, c, d) = ((a - b).abs(), (b - c).abs(), (c - d).abs(), (d - a).abs());
        i += 1;
    }
    i
}

fn main() {
    println!("{}", steps(87759737405187146732, 56850658833245721748, 20866, 104564663817187793641,))
}