/** * Created by kwo2002 on 2015-07-27. */ object UniqueChar { def validUniqueChar(text: String): Boolean = { def go(n: Int, seq: Int, text: String): Boolean = { if (n < text.length && seq < text.length) { if (text.charAt(n) == text.charAt(seq)) { false } else { go(n, seq + 1, text) } } else { if (n + 1 < text.length) { go(n + 1, n + 2, text) } else { true } } } go(0, 1, text) } def main(args: A..