【Rust】簡易的なBloomfilter

ブルームフィルタを更新していくロジックがいまいちわからんが、なんとなく

use std::hash::{DefaultHasher, Hash, Hasher};

#[derive(Debug, PartialEq, Clone)]
struct BloomFilter {
    filter: [i32; 10],
}

impl BloomFilter {
    fn set_v(&mut self, val: String) {
        let list: Vec<u8> = self.n_hash(val);
        for l in list {
            let i = usize::from(l);
            if self.filter[i] == 0 {
                self.filter[i] = 1
            } else {
                self.filter[i] = 2 }
        }    
    }

    fn n_hash(&self, val: String) -> Vec<u8>{
        let hashed = siphash(val);
        let list: Vec<u8> = s_digit(hashed);
        return list
    }

    fn check_v(self, val: String) -> bool {
        let list: Vec<u8> = self.n_hash(val);
        let mut c_bf = BloomFilter { filter: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]};
        for l in list {
            let i = usize::from(l);
            if c_bf.filter[i] == 0 {
                c_bf.filter[i] = 1
            } else {
                c_bf.filter[i] = 2 }
        }
        return self == c_bf
    }
}

fn siphash(s: String) -> u64 {
    let mut siphash = DefaultHasher::new();
    s.hash(&mut siphash);
    return siphash.finish()
}

fn s_digit(n: u64) -> Vec<u8> {
    n.to_string()
        .chars()
        .into_iter()
        .map(|char| char.to_digit(10).unwrap() as u8)
        .collect()
}

fn main(){
    let mut bf = BloomFilter { filter: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]};
    bf.set_v("hello world".to_string());
    println!("{:?}", bf);
    println!("{}", bf.clone().check_v("hello world!".to_string()));
    println!("{}", bf.clone().check_v("hello world".to_string()));
}

Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.33s
Running `target/debug/wallet`
BloomFilter { filter: [2, 2, 0, 1, 2, 1, 1, 2, 2, 2] }
false
true