chutten

use std::env;
use std::fs::File;
use std::io::prelude::*;
use std::io::BufReader;

fn main() {
    let args: Vec<String> = env::args().collect();

    let filename = &args[1];

chutten

use std::io;

fn main() {

  let mut captcha = String::new();
  io::stdin().read_line(&mut captcha)
    .expect("Failed to read line");
  let captcha = captcha.trim();

  let mut chars = captcha.chars().cycle();