Set is a collection of distinct objects. If you try to add two or more objects to the Set that are equal (a == b), the second and subsequent ones are ignored.

As with List, the default creation function for Set (setOf()) creates an immutable Set. Use mutableSetOf() to create a Set that you can modify after creation.

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Accessing Elements via [] any() any() and Short Circuits Array Modification Arrays Combining Collections filter() first() first() Sans Lambda firstOrNull() firstOrNull() and the Elvis Operator fold() for Loop forEach() forEach() is a Function joinToString() Lists map() map() Type Conversions Maps Mutable Lists Sets Typed Arrays
filter() for Loop forEach() forEach() is a Function map() map() Type Conversions Sets
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