Data commit

Task/Kaprekar-numbers/CoffeeScript/kaprekar-numbers.coffee

@@ -0,0 +1,29 @@
+splitAt = (str, idx) ->
+    ans = [ str.substring(0, idx), str.substring(idx) ]
+    if ans[0] == ""
+        ans[0] = "0"
+    ans
+
+getKaprekarParts = (longValue, sqrStr, base) ->
+    for j in [ 0 .. sqrStr.length / 2 ]
+        parts = splitAt(sqrStr, j)
+        nums = (parseInt(n, base) for n in parts)
+
+        # if the right part is all zeroes, then it will be forever, so break
+        if nums[1] == 0
+            return null
+        if nums[0] + nums[1] == longValue
+            return parts
+    null
+
+base = 10
+count = 0
+max = 1000000
+for i in [1..max]
+    i2 = i * i
+    s = i2.toString(base)
+    p = getKaprekarParts i, s, base
+    if p
+        console.log i, i.toString(base), s, p.join '+'
+        count++
+console.log "#{count} Kaprekar numbers < #{max} (base 10) in base #{base}"