@amoszhou
2014-05-07T06:37:36.000000Z
字数 1482
阅读 1876
scala课后习题
def percentMap(map : Map[String,Float])={
for((name,price) <- map) yield (name,price*0.9)
}
def wordCount(file:String)={
val words = Source.fromFile(file).mkString
val wordArray = words.split(" ")
val map = new HashMap[String,Int]
for(word <- wordArray){
map(word)=map.getOrElse(word,0)+1
}
}
def wordCount2(file :String)={
val source = Source.fromFile("myfile.txt").mkString
val tokens = source.split(" ")
var map = Map[String,Int]()
for(key <- tokens){
map += (key -> (map.getOrElse(key,0) + 1))
}
}
这题主要是考LinkedHashMap
val map = new LinkedHashMap[String,Int]
map += ("Monday"->Calendar.MONDAY)
map += ("Tuesday"->Calendar.TUESDAY)
map += ("Wednesday"->Calendar.WEDNESDAY)
map += ("Thursday"->Calendar.THURSDAY)
map += ("Friday"->Calendar.FRIDAY)
map += ("Saturday"->Calendar.SATURDAY)
map += ("Sunday"->Calendar.SUNDAY)
def minmax(values:Array[Int])={
(values.max,values.min)
}
def iteqgt(values:Array[Int],v:Int)={
val buf = values.toBuffer
(values.count(_ < v),values.count(_ == v),values.count(_ > v))
}
scala> "Hello".zip("World")
res0: scala.collection.immutable.IndexedSeq[(Char, Char)] = Vector((H,W), (e,o), (l,r), (l,l), (o,d))
这个主要是去看StringOps里面的zip方法定义。