Scala Map失去了元素？

Question

    val sc = new SparkContext(conf)
    val sqlContext = new org.apache.spark.sql.SQLContext(sc)

    val regex : Regex = """<a href=\\"([^\\\r\n]*)\\">Rubik<\/a>""".r

    val files = "book1"
    val file = sc.textFile(files)
    val rubikLines = file.filter(line => line.contains(">Rubik</a>"))

    val matchedMap = scala.collection.mutable.Map[String,Int]()

    for (line <- rubikLines)
    {
        for (patternMatch <- regex.findAllMatchIn(line)) 
        {
            val ent = patternMatch.group(1)
            if (matchedMap.contains(ent))
            {

                matchedMap(ent) =  (matchedMap(ent)+1)
                println(s"found ${matchedMap(ent)}")
            }
            else
            {

                matchedMap(ent) = 1
                println(s"not found ${matchedMap(ent)}")
            }

        }
        println(s"map size ${matchedMap.size}") //print1
    }

    println(s"map size ${matchedMap.size}") //print2

打印这些语句的结果为[未找到，找到，找到，未找到]，并且对于两个元素[Rubik Cube（已存在3次），ErnőRubik（已存在一次）]是正确的 print1的输出为2，而print2的输出为0。当存在for循环时，为什么matchMap为空？