Refactoring for memory allocation improvement

src/Julia/Problem012.jl

@@ -36,19 +36,11 @@ function Problem12()
     =#
 
     function num_divisors(n)
-        res = floor(Int, sqrt(n))
-        divs = Int[]
-        for i = 1:res
-            if n % i == 0
-                append!(divs, i)
-            end
-        end
-        if res^2 == n
-            pop!(divs)
-        end
-        return 2 * length(divs)
+        r = isqrt(n)
+        2 * count(n % i == 0 for i in 1:r) - (r^2 == n)
     end
     
+
     triangle = 0
     for i in Iterators.countfrom(1)
         triangle += i