Data update

Task/Hailstone-sequence/Bruijn/hailstone-sequence.bruijn

@@ -0,0 +1,21 @@
+:import std/Combinator .
+:import std/List .
+:import std/Math M
+:import std/Number/Binary .
+
+# hailstone sequence using binary shifts
+hailstone y [[(0 =? (+1b)) {}0 go]]
+	go 0 : (=²?0 (1 /²0) (1 (↑¹0 + 0)))
+
+# --- tests ---
+
+seq-27 hailstone (+27b)
+
+:test (∀seq-27) ((+112))
+:test (take (+4) seq-27) ((+27b) : ((+82b) : ((+41b) : {}(+124b))))
+:test (take (+4) <~>seq-27) ((+1b) : ((+2b) : ((+4b) : {}(+8b))))
+
+below-100000 [0 : ∀(hailstone 0)] <$> seq
+	seq take (+99999) (iterate ++‣ (+1b))
+
+main [head (max-by (M.compare ⋔ tail) below-100000)]

Task/Hailstone-sequence/Elena/hailstone-sequence.elena

@@ -36,7 +36,7 @@ public program()
     int longestNumber := 0;
     auto recursiveLengths := new Map<int,int>(4096,4096);
 
-    for(int i := 1, i < maxNumber, i+=1)
+    for(int i := 1; i < maxNumber; i+=1)
     {
         var chainLength := Hailstone(i, recursiveLengths);
         if (longestChain < chainLength)

Task/Hailstone-sequence/Refal/hailstone-sequence.refal

@@ -0,0 +1,42 @@
+$ENTRY Go {
+    = <ShowHailstone 27>
+      <ShowLongest 100000>;
+}
+
+Hailstone {
+    1 = 1;
+    s.N, <Mod s.N 2>: {
+        0 = s.N <Hailstone <Div s.N 2>>;
+        1 = s.N <Hailstone <+ 1 <* 3 s.N>>>;
+    };
+};
+
+ShowHailstone {
+    s.N, <Hailstone s.N>: e.Seq,
+         <Lenw e.Seq>: s.Len s.1 s.2 s.3 s.4 e.X s.D4 s.D3 s.D2 s.D1
+        = <Prout 'The hailstone sequence for the number '
+             <Symb s.N> ' has ' <Symb s.Len> ' elements,\n'
+             'starting with ' s.1 s.2 s.3 s.4
+             'and ending with ' s.D4 s.D3 s.D2 <Symb s.D1>'.'>;
+}
+
+FindLongest {
+    s.Max = <FindLongest s.Max 1 1 1>;
+    s.Max s.Max s.Long s.Len = s.Long s.Len;
+    s.Max s.Cur s.Long s.Len,
+        <Hailstone s.Cur>: e.CurSeq,
+        <Lenw e.CurSeq>: s.CurLen e.X,
+        <+ s.Cur 1>: s.Next,
+        <Compare s.CurLen s.Len>: {
+            '+' = <FindLongest s.Max s.Next s.Cur s.CurLen>;
+            s.X = <FindLongest s.Max s.Next s.Long s.Len>;
+        };
+};
+
+ShowLongest {
+    s.Max, <FindLongest s.Max>: s.Long s.Len
+        = <Prout 'The number < ' <Symb s.Max> ' which has the longest'
+                 ' hailstone sequence is ' <Symb s.Long> '.\n'
+                 'The length of its Hailstone sequence is '
+                 <Symb s.Len> '.'>;
+};