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use std::collections::HashMap;

fn main() {
    //let v: Vec<i32> = Vec::new();
    //let mut v = vec![1, 2, 3, 4, 5];

    //    let third: &i32 = &v[2];
    //    println!("the third element is {}", third);
    //
    //    match v.get(2) {
    //        Some(third) => println!("third is {}", third),
    //        None => println!("no third element"),
    //    }
    //
    // for i in &mut v {
    //     *i += 10;
    //     println!("{}", *i);
    // }
    //   for i in &v {
    //       println!("{}", i);
    //   }

    //    enum SpreadsheetCell {
    //        Int(i32), 
    //        Float(f64),
    //        Text(String), 
    //    }
    //
    //    let row = vec![
    //        SpreadsheetCell::Int(3),
    //        SpreadsheetCell::Text(String::from("blue")),
    //        SpreadsheetCell::Float(10.12),
    //    ];

    //let mut s = String::new();

    //let data = "initial contents";
    //let s = data.to_string();
    //dbg!(s);
    //let s = "initial contents".to_string();
    //dbg!(s);
    //let s = String::from("initial contents");
    //dbg!(s);

    //let mut s = String::from("hello");
    //s.push_str(" world");

    //let mut s1 = String::from("hello");
    //let s2 = " world";
    //s1.push_str(s2);
    //s1.push('!');
    //dbg!(s1);

    //let s1 = String::from("Hello ");
    //let s2 = String::from("world");
    //let s3 = s1 + &s2 + "!";
    //dbg!(s3);

    //let my_result: Result<&'static str, &'static str> = Ok("test");

    //dbg!(my_result);

    //let s1 = String::from("tic");
    //let s2 = String::from("tac");
    //let s3 = String::from("toe");

    //let s = format!("{}-{}-{}", s1, s2, s3);
    //dbg!(s);

    //let s = String::from("welcome to hello world");
    //let len = s.len();
    //dbg!(len);
    //let s1 = s[0..15].to_string();
    //dbg!(s1);

    //for c in "hello world".bytes() {
    //    dbg!(c);
    //}

    //let mut scores = HashMap::new();
    //scores.insert(String::from("Blue"), 10);
    //scores.insert(String::from("Yellow"), 50);
    //scores.insert(String::from("Blue"), 20);
    //dbg!(scores);

    //let teams = vec![String::from("blue"), String::from("yellow")];
    //let initial_scores = vec![10, 20];
    //let scores: HashMap<_, _> = teams.iter().zip(initial_scores.iter()).collect();
    //dbg!(scores);

    //let field_name = String::from("favorite color");
    //let field_value = String::from("blue");

    //let mut map = HashMap::new();
    //map.insert(field_name, field_value);

    //let mut scores = HashMap::new();
    //scores.insert(String::from("blue"), 10);
    //scores.insert(String::from("yellow"), 50);

    //let team_name = String::from("blue");
    //let score = scores.get(&team_name);

    //dbg!(team_name);
    //dbg!(score);

    //let mut scores = HashMap::new();

    //scores.insert(String::from("blue"), 10);
    //scores.insert(String::from("yellow"), 50);

    //for (key, value) in &scores {
    //    dbg!(key);
    //    dbg!(value);
    //}

    // let mut scores = HashMap::new();
    // scores.insert(String::from("blue"), 10);
    // scores.entry(String::from("yellow")).or_insert(50);
    // scores.entry(String::from("blue")).or_insert(50);
    // dbg!(scores);

    //let text = "when in the course of himan events it becomes necessary for one people to dissolve the political bands which have connected them with another and to assume among the powers of the earth the separate and equal station to which thelaws of nature and of nature's God entitle them a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation";
    //let mut map = HashMap::new();

    //for word in text.split_whitespace() {
    //    let count = map.entry(word).or_insert(0);
    //    *count += 1;
    //}

    //dbg!(map);

}