problem 85 in julia

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diff --git a/julia/085-counting_rectangles.jl b/julia/085-counting_rectangles.jl
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+###
+# Counting rectangles
+# Problem 85
+#
+# By counting carefully it can be seen that a rectangular grid measuring 3 by 2 contains
+# eighteen rectangles:
+# Although there exists no rectangular grid that contains exactly two million rectangles,
+# find the area of the grid with the nearest solution.
+###
+
+
+# blackpenredpend: https://www.youtube.com/watch?v=Uq9OXC0Gzgw
+
+using Base.Iterators
+
+
+const TARGET_RECTANGLES = 2_000_000
+
+combinations_2(n) = (n * (n - 1)) / 2
+dist = Inf
+for width in countfrom(1), height in 1:width
+    count = combinations_2(width + 1) * combinations_2(height + 1)
+    global dist = min(dist, abs(TARGET_RECTANGLES - count))
+    if dist < 3  # I just tested a bunch of different threshold
+        println(width * height)
+        break
+    end
+end