Wrong counter in hashmap

help
1

I have a vector u8, and I try to count the number that occurs the maximum number of times:

use std::collections::HashMap;

fn main() {
    let v:Vec<u8> = vec![1,2,3,6,7,8,9,4,3,5,4,6,7,8,3,5,6,2,3,4,5,6,7,5,6];
    let a = exercise1(v);
    println!("average - {}, middle - {}, max_count key - {}",a[0],a[1],a[2])
    //println!("vec = {:?}",v);
}

pub fn exercise1(v: Vec<u8>) -> [u8; 3] {
    let mut sum: u8 = 0;
    let mut i = 0;
    let mut map = HashMap::new();
    for number in v.iter() {
        sum += number;
        i += 1;
        let count = map.entry(number).or_insert(0);
        *count +=1;
    }
    let average = sum/i as u8;
    let j = i/2;
    println!("{:?}", map);    
    
    let mut max_count: u8 =0;
    for (_key, value) in &map {
        //println!("{:?}:{:?}",key,value);
        if value > &max_count {
            max_count = *value;
        }
    }
    
    println!("max_count = {:?}", max_count);
    
    let mut max_key: u8 = 0;
    for (_key, value) in &map {
        //println!("{:?}:{:?}",key,value);
        if value == &max_count {
            max_key = **_key;
        }
    }

    let a: [u8; 3]=[average,v[j],max_key];
    return a;
}

If I run the script:

eyegor@twdevel:~/devel/rust/study/exercises/exercise1$ cargo run
    Finished dev [unoptimized + debuginfo] target(s) in 0.01s
     Running `target/debug/exercise1`
{3: 4, 8: 2, 5: 4, 7: 3, 2: 2, 1: 1, 9: 1, 4: 3, 6: 5}
max_count = 5
average - 5, middle - 7, max_count key - 6

I've see, that max_count is 5 of number 6, but realy number 6 occurs only 4 times. Where is my misstake?

2

That seems to be wrong. Here's the playground illustrating it.

3

Realy. Thank You!

4

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