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Task/Stem-and-leaf-plot/Sidef/stem-and-leaf-plot.sidef

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+var data = %i(
+     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
+).sort;
+
+var stem_unit = 10;
+var h = data.group_by { |i| i / stem_unit -> int }
+
+var rng = RangeNum(h.keys.map{.to_i}.minmax);
+var stem_format =  "%#{rng.min.len.max(rng.max.len)}d";
+
+rng.each { |stem|
+    var leafs = (h{stem} \\ [])
+    say(stem_format % stem, ' | ', leafs.map { _ % stem_unit }.join(' '))
+}