kotlin 指定文字列の出現数をカウント

gistfile1.txt

// 指定文字列の出現数をカウント
fun main(args: Array<String>) {
    var str:String = "WWWDDLLLDDDWWWDDDDDLLLDLWDWLDDDD"
    var len = { str: String -> str.length }
    println("$str, %d".format(len(str)))
    var findstrlist = listOf("DDDDD", "DDDD", "DDD") 
    for(findstr: String in findstrlist) {
        var len1 = str.length
        str = str.replace(findstr, "")
        var len2 = str.length
        var count = (len1 - len2) / findstr.length
        println("$findstr, $count")
    }
}