Solution for another dojo at FPF

pizza.rs

use std::collections::HashMap;
use std::num::abs;

pub struct Preference {
    name: String,
    flavors: HashMap<String, int>
}

impl Preference {
    pub fn compare_preference<'a>(&'a self, preferences: &'a[Preference]) -> Option<&'a str> {
        let mut preference = None;
        let mut menor_total = 10000; // such woowww
        for pref in preferences.iter() {
            let mut total = 0;
            for (key, value) in self.flavors.iter(){
                total += abs(pref.flavors.get(key) - *value);
            }
            if menor_total > total {
                preference = Some(pref);
                menor_total = total;
            }
        }
        preference.map(|result| result.name.as_slice())
    }
}

mod test {
    use std::collections::HashMap;
    use super::Preference;

    #[test]
    fn test_preference() {
        let mut flavors = HashMap::new();
        flavors.insert(String::from_str("Mussarela"),3 );
        flavors.insert(String::from_str("Toscana"),5 );
        flavors.insert(String::from_str("Sertaneja"),1 );

        let fulano = Preference {
            name: String::from_str("Fulano"),
            flavors: flavors
        };

        let mut flavors = HashMap::new();
        flavors.insert(String::from_str("Mussarela"),3 );
        flavors.insert(String::from_str("Toscana"),5);
        flavors.insert(String::from_str("Sertaneja"),1);

        let ciclano = Preference{
            name: String::from_str("ciclano"),
            flavors: flavors
        };

        let mut flavors = HashMap::new();
        flavors.insert(String::from_str("Mussarela"),1);
        flavors.insert(String::from_str("Toscana"),1 );
        flavors.insert(String::from_str("Sertaneja"),1 );

        let beltrano = Preference{
            name: String::from_str("Beltrano"),
            flavors: flavors
        };

        let pessoas = vec![ciclano,beltrano];

        assert_eq!(fulano.compare_preference(pessoas.as_slice()), Some("ciclano"));


    }
}

pizza2.rs

use std::collections::HashMap;

pub struct Preference {
    name: String,
    flavors: HashMap<String, int>
}

impl Preference {
    pub fn compare_preference<'a>(&'a self, preferences: &'a[Preference])
                                  -> Option<&'a str> {
        preferences.iter().min_by(|pref| self.flavors.iter()
                                  .fold(0, |x, (key,value)|
                                        x+(pref.flavors.get(key) - *value).abs()))
            .map(|pref| pref.name.as_slice())
    }
}

mod test {
    use std::collections::HashMap;
    use super::Preference;

    #[test]
    fn test_preference() {
        let mut flavors = HashMap::new();
        flavors.insert(String::from_str("Mussarela"), 3);
        flavors.insert(String::from_str("Toscana"), 5);
        flavors.insert(String::from_str("Sertaneja"), 1);

        let fulano = Preference {
            name: String::from_str("Fulano"),
            flavors: flavors
        };

        let mut flavors = HashMap::new();
        flavors.insert(String::from_str("Mussarela"), 4);
        flavors.insert(String::from_str("Toscana"), 5);
        flavors.insert(String::from_str("Sertaneja"), 1);

        let ciclano = Preference{
            name: String::from_str("ciclano"),
            flavors: flavors
        };

        let mut flavors = HashMap::new();
        flavors.insert(String::from_str("Mussarela"), 1);
        flavors.insert(String::from_str("Toscana"), 1);
        flavors.insert(String::from_str("Sertaneja"), 1);

        let beltrano = Preference{
            name: String::from_str("Beltrano"),
            flavors: flavors
        };

        let pessoas = vec![ciclano,beltrano];

        assert_eq!(fulano.compare_preference(pessoas.as_slice()), Some("ciclano"));


    }
}