from itertools import (groupby) from functools import (reduce) # stemLeaf :: (String -> Int) -> (String -> String) -> String -> String def stemLeaf(f, g, s): return '\n'.join(map( lambda x: str(x[0]).rjust(2) + ' | ' + reduce(lambda a, tpl: a + tpl[1] + ' ', x[1], ''), (groupby(sorted( map(lambda x: (f(x), g(x)), s.split()) ), lambda x: x[0] )) )) # main :: IO() def main(): def stem(s): return (lambda x=s[:-1]: int(x) if 0 < len(x) else 0)() def leaf(s): return s[-1] s = ('12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31' ' 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23' ' 105 63 27 44 105 99 41 128 121 116 125 32 61 37 127 29 113 121 58' ' 114 126 53 114 96 25 109 7 31 141 46 13 27 43 117 116 27 7 68 40' ' 31 115 124 42 128 52 71 118 117 38 27 106 33 117 116 111 40 119 47' ' 105 57 122 109 124 115 43 120 43 27 27 18 28 48 125 107 114 34 133' ' 45 120 30 127 31 116 146') print (stemLeaf(stem, leaf, s)) main()