====== Sunday, May 15th 2022 ======

==== k =====
have you play this game? [[https://store.steampowered.com/app/1154810/Going_Under/|this]]. its pretty funny.

===== Collections =====

Collections are like arrays or tuples whose size do not need to be known at compile time. The two types are

  - Vectors
  - HashMap (like Dictionaries in c#)


==== Vectors ==== 
Vectors are resizable arrays whos length do not need to be known at compile time but the size of its type needs to be known.

You can init a vector with the vec! macro. eg

<code rust> let x = vec![20,50,20]; </code>

You can access a certain element like <del>dish</del> <del>rish</del> **this***

<code rust> println!("{}",x[0]);  </code>

You can iterate through every value like <del>dish</del> <del>rish</del> **this*** ((haha, I'm so quirky))

[[https://doc.rust-lang.org/stable/rust-by-example/std/vec.html|stolen from the rust by example book]]
<code rust> 
// `Vector`s can be easily iterated over
println!("Contents of xs:");
for v in x.iter() {
 println!("> {}", x);
}

// A `Vector` can also be iterated over while the iteration
// count is enumerated in a separate variable (`i`)
for (i, v) in x.iter().enumerate() {
 println!("In position {} we have value {}", i, x);
}

// Thanks to `iter_mut`, mutable `Vector`s can also be iterated
// over in a way that allows modifying each value
for v in xs.iter_mut() {
 *v *= 3;
}
println!("Updated vector: {:?}", xs);
</code>

==== HashMap ====

Like dictionaries these use key value pairs. 

To make one
<code rust>
let mut name_and_age = HashMap::new();

name_and_age.insert("Gassica",22);
name_and_age.insert("Alex",12);

name_and_age.get("Alex") //ACCESSING THE VALUE
</code>

You can also insert "entry"

<code rust>
name_and_age.entry(String::from("thomas")).or_insert(20); //Insert only if unique
</code>

which is bascially insert if unique. The aims to finish this by may atleast. (given I spend only a little time a week on it) will prollly do some exercizes thru the week without typing my noon-sense.((but typing this is fun fun fun fun)).

{{:devlogs:rustlings_excersizes.png?direct&400|}}