Zeckendorf in Rust

Welcome to the Zeckendorf in Rust page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

use std::cmp::PartialOrd;
use std::env::args;
use std::ops::{Add, SubAssign};
use std::process::exit;
use std::str::FromStr;

fn usage() -> ! {
    println!("Usage: please input a non-negative integer");
    exit(0);
}

fn parse_int<T: FromStr>(s: &str) -> Result<T, <T as FromStr>::Err> {
    s.trim().parse::<T>()
}

fn get_fibonacci_values<T>(value: T) -> Vec<T> 
where 
    T: Add<Output = T> + PartialOrd + From<u8> + Copy 
{
    let mut fibs = vec![];
    let mut a: T = T::from(1);
    let mut b: T = T::from(2);
    while a <= value {
        fibs.push(a);
        (a, b) = (b, a + b);
    }

    fibs
}

fn get_zeckendorf_values<T>(value: T) -> Vec<T>
where 
    T: Add<Output = T> + SubAssign + PartialOrd + From<u8> + Copy 
{
    let fibs = get_fibonacci_values(value);
    let mut zecks = vec![];
    let mut n = (fibs.len() as i32) - 1;
    let mut remaining = value;
    while n >= 0 && remaining > T::from(0) {
        let f = fibs[n as usize];
        if remaining >= f {
            zecks.push(f);
            remaining -= f;
            n -= 2;
        } else {
            n -= 1;
        }
    }

    zecks
}

fn main() {
    let mut args = args().skip(1);

    // Exit if 1st command-line argument not an integer
    let input_num: i32 = args
        .next()
        .and_then(|s| parse_int(&s).ok())
        .unwrap_or_else(|| usage());

    // Exit if value is negative
    if input_num < 0 {
        usage();
    }

    let zecks = get_zeckendorf_values::<i32>(input_num);
    println!("{:?}", zecks);
}

Zeckendorf in Rust was written by:

• rzuckerm

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

No 'How to Run the Solution' section available. Please consider contributing.