Ira Glass’s advice for beginners:

# Tag: learning

## Scala Hacking: Computing min and max of a List

There are several ways to accomplish this. Next code snippet shows how to compute min and max using `reduceLeft`

.

val ls = List(1,2,3,4,5) ls.reduceLeft(_ min _) // is equivalent to ls.min ls.reduceLeft(_ max _) // is equivalent to ls.max

Same can be accomplished via `foldLeft`

or `foldRight`

.

ls.foldLeft(Int.MaxValue) (_ min _) ls.foldLeft(Int.MinValue) (_ max _)

However, can we compute both min and max in one line? Check out the following snippet.

ls.map( x=>(x,x)).reduceLeft( (x,y) => (x._1 min y._1, x._2 max y._2)

An alternative is to use `foldLeft`

:

ls.foldLeft ((Int.MaxValue, Int.MinValue)) ((acc:(Int,Int),y:Int) => (acc._1 min y, acc._2 max y))