fun findSubstrings(text: String, substring: String) : MutableList<Int> {
    var ret = mutableListOf<Int>();
    var muttext = text;
    var mutsubstring = substring;
    var i = 0
    while (i + mutsubstring.length <= muttext.length) {
        //print(muttext.substring(i, i + mutsubstring.length))
        if (muttext.substring(i, i + mutsubstring.length) == mutsubstring) {
            ret.add(i);
            i += mutsubstring.length;
        } else {
            i += 1
        }
    }

    return ret;
}