Improve performance

src/Julia/Problem012.jl

@@ -36,17 +36,17 @@ function Problem12()
     =#
 
     function num_divisors(n)
-        res = floor(sqrt(n))
+        res = floor(Int, sqrt(n))
         divs = []
-        for i in 1:res
+        for i = 1:res
-            if n%i == 0
+            if n % i == 0
-                append!(divs,i)
+                append!(divs, i)
             end
         end
         if res^2 == n
             pop!(divs)
         end
-        return 2*length(divs)
+        return 2 * length(divs)
     end
 
     triangle = 0