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elan lane lean lena neal
evil levi live veil vile
=={{header|Scala}}==
'''Compiler:''' [[scala]] (2.7.5)
[[Category:Scala]]
{{libheader|scala.collection.mutable}}
<lang scala>
import scala.io.Source
import scala.collection.mutable
object Anagrams{
</lang>
We can start with a most superficial method - one for printing a list of Strings. This method prints a given list of Strings
in a line , each separated by a "|". Each such list represents one set of anagrams
<lang scala>
def printList(strLst : List[String]) {
print("|")
strLst.foreach(x => print(x + "|"))
println("")
}
</lang>
Every String has a "root", which is a String which has all the characters in it alphabetically arranged. For example,
the root for the string "string" is the string "ginrst". The root for "root" is "oort".
<lang scala>
def rootString(str:String):String = new String(str.trim.toCharArray.toList.sort(_<_).toArray)
</lang>
We need a method that takes a string and a mutable map between the Strings and List of Strings. Given a String, we compute
the root of the String and then check if the root is existing as a key in the map. If it does , we append the given string
to the value mapped to that key. Otherwise, we insert the key into the map with the value as a new singleton list containing
just the given String
<lang scala>
def handleString(str:String,strMap:mutable.Map[String,List[String]]){
val root = rootString(str)
(strMap.get(root)) match{
case Some(lst) => strMap.update(root,str.trim::lst)
case None => strMap.update(root,List(str.trim))
}
}
</lang>
Finally, we need the main method that creates an empty map, reads the contents of the file line and by line and appends the
map. Then we iterate over the values of the map and prints them
<lang scala>
def main(args:Array[String]){
val fileName = "unixdict.txt"
val strmap = new mutable.HashMap[String, List[String]]
Source.fromFile(fileName).getLines.foreach(x => handleString(x,strmap))
strmap.values.foreach(printList)
}
}
</lang>
Sample output is given below:
|mental|mantle|mantel|lament|
|vocate|octave|avocet|
|organ|groan|argon|
| |||