Counter

warning: unused import: `std::cmp::min`
 --> input/code.rs:1:5
  |
1 | use std::cmp::min;
  |     ^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

warning: denote infinite loops with `loop { ... }`
  --> input/code.rs:35:5
   |
35 |     while true {
   |     ^^^^^^^^^^ help: use `loop`
   |
   = note: `#[warn(while_true)]` on by default

warning: 2 warnings emitted

use std::cmp::min;
use std::io::{self, Read};

macro_rules! input {
    ($it: expr) => {
        $it.next().unwrap().parse().unwrap()
    };
    ($it: expr, $T: ty) => {
        $it.next().unwrap().parse::<$T>().unwrap()
    };
}
/*
mod classes;
mod homework;

fn main() {
    // println!("{}", "-".repeat(20));
    classes::c24::task_g();
    // homework::hw9::task1();
    // println!("{}", "-".repeat(20));
}
// */

fn main() {
    let mut buf = String::new();
    io::stdin().read_to_string(&mut buf).unwrap();

    let mut it = buf.split_whitespace();

    let x: usize = input!(it);

    let mut steps: usize = 0;
    let mut counter: usize = 0;

    while true {
        if counter == x {
            println!("{}", steps);
            return;
        }
        else if counter + 11 <= x {
            counter += 11;
        } else if counter >= 2 {
            counter -= 2;
        } else {
            println!("-1");
            return;
        }
        steps +=1;
    }
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED