Section 9-3: Data Structures, Modern Operators and Strings

115. Sets

But anyway, keep in mind that strings are also iterables.

116. Maps: Fundamentals

So just like an object,

data is stored in key value pairs in maps. Now the big difference between objects and maps, is that in maps, the keys can have any type.

And this can be huge.

So in objects, the keys are basically always strings.

But in maps, we can have any type of key.

117. Maps Iteration.

118. Summary: Which Data Structure to Use?

120. Working with String 1
     
     slice- So basically it's the position at which the extraction will start. 예시) 4번쨰부터 출력

airline.slice(4,7) 4번째부터 7번째까지 = Air
airline.slice(-2) 뒤에서 2번째 al
airline.slice(1,-1) Ap Air Portuga 앞에하나 뒤에하나

trim.() 빈공간 없애는것.

replaceAll 나중에 추가되는듯?

join('--') 이런식으로도가능

same result