mirror of
https://github.com/uutils/coreutils
synced 2024-12-16 00:02:50 +00:00
108 lines
2.6 KiB
Rust
108 lines
2.6 KiB
Rust
#![crate_id(name="factor", vers="1.0.0", author="T. Jameson Little")]
|
|
#![feature(macro_rules)]
|
|
|
|
/*
|
|
* This file is part of the uutils coreutils package.
|
|
*
|
|
* (c) T. Jameson Little <t.jameson.little@gmail.com>
|
|
*
|
|
* For the full copyright and license information, please view the LICENSE file
|
|
* that was distributed with this source code.
|
|
*/
|
|
|
|
extern crate getopts;
|
|
extern crate libc;
|
|
|
|
use std::u64;
|
|
use std::os;
|
|
use std::vec::{Vec};
|
|
use std::io::{stdin};
|
|
|
|
#[path="../common/util.rs"]
|
|
mod util;
|
|
|
|
static VERSION: &'static str = "1.0.0";
|
|
static NAME: &'static str = "factor";
|
|
|
|
fn factor(mut num: u64) -> Vec<u64> {
|
|
let mut ret = Vec::new();
|
|
|
|
if num < 2 {
|
|
return ret;
|
|
}
|
|
while num % 2 == 0 {
|
|
num /= 2;
|
|
ret.push(2);
|
|
}
|
|
let mut i = 3;
|
|
while i * i <= num {
|
|
while num % i == 0 {
|
|
num /= i;
|
|
ret.push(i);
|
|
}
|
|
i += 2;
|
|
}
|
|
if num > 1 {
|
|
ret.push(num);
|
|
}
|
|
ret
|
|
}
|
|
|
|
fn print_factors(num: u64) {
|
|
print!("{}:", num);
|
|
for fac in factor(num).iter() {
|
|
print!(" {}", fac);
|
|
}
|
|
println!("");
|
|
}
|
|
|
|
fn print_factors_str(num_str: &str) {
|
|
let num = match u64::parse_bytes(num_str.as_bytes(), 10) {
|
|
Some(x) => x,
|
|
None => { crash!(1, "{} not a number", num_str); }
|
|
};
|
|
print_factors(num);
|
|
}
|
|
|
|
|
|
#[allow(dead_code)]
|
|
fn main() { uumain(os::args()); }
|
|
|
|
pub fn uumain(args: Vec<String>) {
|
|
let program = args.get(0).as_slice();
|
|
let opts = [
|
|
getopts::optflag("h", "help", "show this help message"),
|
|
getopts::optflag("v", "version", "print the version and exit"),
|
|
];
|
|
|
|
let matches = match getopts::getopts(args.tail(), opts) {
|
|
Ok(m) => m,
|
|
Err(f) => crash!(1, "Invalid options\n{}", f)
|
|
};
|
|
|
|
if matches.opt_present("help") {
|
|
print!("{program} {version}\n\
|
|
\n\
|
|
Usage:\n\
|
|
\t{program} [NUMBER]...\n\
|
|
\t{program} [OPTION]\n\
|
|
\n\
|
|
{usage}", program = program, version = VERSION, usage = getopts::usage("Print the prime factors of the given number(s). \
|
|
If none are specified, read from standard input.", opts));
|
|
return;
|
|
}
|
|
if matches.opt_present("version") {
|
|
println!("{} {}", program, VERSION);
|
|
return;
|
|
}
|
|
|
|
if matches.free.is_empty() {
|
|
for line in stdin().lines() {
|
|
print_factors_str(line.unwrap().as_slice().trim());
|
|
}
|
|
} else {
|
|
for num_str in matches.free.iter() {
|
|
print_factors_str(num_str.as_slice());
|
|
}
|
|
}
|
|
}
|