Finish factor utility

factor.nim

@@ -1,11 +1,19 @@
-import cligen
+import cligen, sequtils
 import common
 
 proc factor(num:int):seq[int] =
-    result = @[0]
+    result = @[]
+    var i = num
+    while i > 1:
+        for x in 2..i:
+            if i mod x == 0:
+                result.add(x)
+                i = i div x
+                break
 
 proc main(integers:seq[int]) =
     for number in integers:
-        echo number, ": ", factor(number)
+        echo number, ": ",
+             map(factor(number), proc(x:int):string = $x & " ").foldl(a & b)
 
 dispatch(main)