use std::time::Instant;

fn get_char_by_bytes(val: &String, index: usize) -> char {
    val.as_bytes()[index] as char
}

fn get_nth_character(val: &String, index: usize) -> char {
    val.chars().nth(index).unwrap()
}

fn main() {
    let word = String::from("Hello world").repeat(1000);
    // let index = 10usize;
    // let answer = 'o';
    let time_limits = (3..=7).map(|x| 10u32.pow(x));
    let time_limit = time_limits.into_iter().nth(0).unwrap();
    for index in 990..1000 {
        println!("For iteration {}, index {}", time_limit, index);
        let now = Instant::now();
        for _ in 0..time_limit {
            get_char_by_bytes(&word, index);
        }
        let elapsed = now.elapsed();
        println!("Elapsed time for bytes {:2?}", elapsed);

        let now = Instant::now();
        for _ in 0..time_limit {
            get_nth_character(&word, index);
        }
        let elapsed2 = now.elapsed();
        println!("Elapsed time for nth character {:2?}", elapsed2);

        println!(
            "Ratio of slowdown {:.2}",
            ((elapsed2.as_micros() as f64) / (elapsed.as_micros() as f64))
        );
    }
}