Robotti

use rand::prelude::*;

fn main() {
    let debug_mode = std::env::args().any(|x| x == "debug".to_string());
    let auto = std::env::args().any(|x| x == "auto".to_string());

    let mut n: String = "".into();
    std::io::stdin().read_line(&mut n).expect("IO Ongelma :(");
    let n: usize = n.trim().parse().expect("Eka rivi ei ollut numero");

    let mut line: String = "".into();

    if !auto {
        // **..**..R..** juttu
        std::io::stdin()
            .read_line(&mut line)
            .expect("IO Ongelma :(");
    } else {
        let mut rng = rand::thread_rng();
        for _ in 0..n {
            let num = rng.gen_range(0.0..=1.);
            if num < 0.3 {
                line.push('*');
            } else {
                line.push('.');
            }
        }

        let half = n / 2;
        line.replace_range(half..=half, "R");
    }

    let mut askeleet = 0;
    let mut kolikot = 0;

    let mut robotti_pos = pos_of_c(&line, 'R')
        .first()
        .expect("Ei R:ää (robottia)")
        .clone();
    let mut kolikko_positions = pos_of_c(&line, '*').clone();

    let time = get_timer();
    while let Some(close) = closest(&robotti_pos, &kolikko_positions) {
        let diff = close as i32 - robotti_pos as i32;
        askeleet += diff.abs();
        robotti_pos = (robotti_pos as i32 + diff) as usize;
        kolikot += 1;
        kolikko_positions.retain(|x| *x != close);
    }

    println!("{} {}", askeleet, kolikot);
    if debug_mode {
        println!("Kesti {}", get_timer() - time);
    }
}

// Pakko alkaa mittaamaan ku ei kelvannu mun 0.2 sekuntia
// Kestävä ratkasu
fn get_timer() -> f64 {
    std::time::SystemTime::now()
        .duration_since(std::time::UNIX_EPOCH)
        .expect("Time went backwards")
        .as_secs_f64()
}

#[inline(always)]
fn closest(a: &usize, b: &[usize]) -> Option<usize> {
    if b.is_empty() {
        return None;
    }

    let mut min_dist = usize::MAX;
    let mut min_pos = 0;
    let mut has_duplicate = false;

    for &pos in b {
        let dist = a.abs_diff(pos);
        match dist.cmp(&min_dist) {
            std::cmp::Ordering::Less => {
                min_dist = dist;
                min_pos = pos;
                has_duplicate = false;
            }
            std::cmp::Ordering::Equal => {
                has_duplicate = true;
            }
            std::cmp::Ordering::Greater => {}
        }
    }

    if has_duplicate {
        None
    } else {
        Some(min_pos)
    }
}

fn pos_of_c(s: &str, c: char) -> Vec<usize> {
    // *
    let mut pos = Vec::with_capacity(s.len());

    for (i, char) in s.chars().enumerate() {
        if char == c {
            pos.push(i);
        }
    }

    pos
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: ACCEPTED

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 1, 2

Verdict: ACCEPTED

Test 8

Group: 1, 2

Verdict: ACCEPTED

Test 9

Group: 1, 2

Verdict: ACCEPTED

Test 10

Group: 1, 2

Verdict: ACCEPTED

Test 11

Group: 1, 2

Verdict: ACCEPTED

Test 12

Group: 2

Verdict: ACCEPTED

Test 13

Group: 2

Verdict: ACCEPTED

Test 14

Group: 2

Verdict: ACCEPTED

Test 15

Group: 2

Verdict: ACCEPTED

Test 16

Group: 2

Verdict: ACCEPTED

Test 17

Group: 2

Verdict: ACCEPTED

Test 18

Group: 2

Verdict: ACCEPTED

Test 19

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 20

Group: 2

Verdict: ACCEPTED

Test 21

Group: 2

Verdict: ACCEPTED

Test 22

Group: 2

Verdict: ACCEPTED

Test 23

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 24

Group: 2

Verdict: TIME LIMIT EXCEEDED