Merkkijonot

warning: unused variable: `key`
  --> input/code.rs:63:10
   |
63 |     for (key, lkm) in mjono_luokat.iter() {
   |          ^^^ help: consider prefixing with an underscore: `_key`
   |
   = note: #[warn(unused_variables)] on by default

warning: function `nCr` should have a snake case name
  --> input/code.rs:10:4
   |
10 | fn nCr(n: u32, k: u32) -> u32 {
   |    ^^^ help: convert the identifier to snake case: `n_cr`
   |
   = note: #[warn(non_snake_case)] on by default

use std::collections::HashMap;

fn fact(n: u32) -> u32 {
    match n {
        0 => 1,
        _ => n * fact(n - 1)
    }
}

fn nCr(n: u32, k: u32) -> u32 {
    if k > n {
        return 0;
    }
    return fact(n) / (fact(k) * fact(n - k));
}

fn main() {
    let mut mjonot_lkm_str = String::new();

    std::io::stdin().read_line(&mut mjonot_lkm_str).unwrap();

    let mjonot_lkm = mjonot_lkm_str.trim().parse::<usize>().unwrap();

    let mut mjono_luokat: HashMap<String, usize> = HashMap::new();

    for _ in 0..mjonot_lkm {
        let mut alku_mjono = String::new();
        std::io::stdin().read_line(&mut alku_mjono).unwrap();
        alku_mjono = alku_mjono.trim().to_string();

        let mut korvatut = std::vec::Vec::new();
        let mut loppu_mjono: std::vec::Vec<u8> = std::vec::Vec::new();
        for alku_mjono_char in alku_mjono.as_bytes() {
            loppu_mjono.push(*alku_mjono_char);
        }

        let mut i = b'A';
        for mjono_char in alku_mjono.as_bytes() {
            if korvatut.contains(&mjono_char) {
                continue;
            }
            korvatut.push(mjono_char);

            let mut j = 0;
            loppu_mjono = alku_mjono.as_bytes().iter().map(|alku_char| {
                if alku_char == mjono_char {
                    j += 1;
                    return i as u8;
                }
                j += 1;
                return loppu_mjono[j - 1];
            }).collect();
            i += 1;
        }

        let avain = String::from_utf8(loppu_mjono).unwrap();
        mjono_luokat.entry(avain)
            .and_modify(|lkm| { *lkm += 1 })
            .or_insert(1);
    }

    let mut kokonais_lkm = 0;
    for (key, lkm) in mjono_luokat.iter() {
        //dbg!(key, lkm);
        kokonais_lkm += nCr(*lkm as u32, 2);
    }
    println!("{}", kokonais_lkm);
}

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 2, 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 3

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 4

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 5

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 6

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 7

Group: 1, 2, 3

Verdict: ACCEPTED

Test 8

Group: 1, 2, 3

Verdict: ACCEPTED

Test 9

Group: 1, 2, 3

Verdict: ACCEPTED

Test 10

Group: 2, 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 11

Group: 2, 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 12

Group: 2, 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 13

Group: 2, 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 14

Group: 2, 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 15

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 16

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 17

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 18

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 19

Group: 3

Verdict: RUNTIME ERROR

thread 'main' panicked at 'attempt to divide by zero', input/code.rs:14:12
note: Run with...

Test 20

Group: 1, 2, 3

Verdict: ACCEPTED

Test 21

Group: 1, 2, 3

Verdict: ACCEPTED

Test 22

Group: 1, 2, 3

Verdict: ACCEPTED

Test 23

Group: 1, 2, 3

Verdict: ACCEPTED

Test 24

Group: 1, 2, 3

Verdict: ACCEPTED