Data commit

Task/Happy-numbers/Icon/happy-numbers.icon

@@ -0,0 +1,17 @@
+procedure main(arglist)
+local n
+n := arglist[1] | 8    # limiting number of happy numbers to generate, default=8
+writes("The first ",n," happy numbers are:")
+every writes(" ", happy(seq()) \ n )
+write()
+end
+
+procedure happy(i)    #: returns i if i is happy
+local n
+
+    if  4 ~= (0 <= i) then { # unhappy if negative, 0, or 4
+        if i = 1 then return i
+        every (n := 0) +:= !i ^ 2
+        if happy(n) then return i
+        }
+end