Data commit

Task/Happy-numbers/BCPL/happy-numbers.bcpl

@@ -0,0 +1,25 @@
+get "libhdr"
+
+let sumdigitsq(n) =
+    n=0 -> 0, (n rem 10)*(n rem 10)+sumdigitsq(n/10)
+
+let happy(n) = valof
+$(  let seen = vec 255
+    for i = 0 to 255 do i!seen := false
+    $(  n!seen := true
+        n := sumdigitsq(n)
+    $) repeatuntil n!seen
+    resultis 1!seen
+$)
+
+let start() be
+$(  let n, i = 0, 0
+    while n < 8 do
+    $(  if happy(i) do
+        $(  n := n + 1
+            writef("%N ",i)
+        $)
+        i := i + 1
+    $)
+    wrch('*N')
+$)