scala> val list = List((1, 'c'), (1, 'b'), (2, 'a'))
list: List[(Int, Char)] = List((1,c), (1,b), (2,a))

scala> val srt1 = list.sortWith(_._2 < _._2)
srt1: List[(Int, Char)] = List((2,a), (1,b), (1,c))

scala> val srt2 = srt1.sortBy(_._1)