problem 62 julia

1 files changed, 32 insertions, 0 deletions

diff --git a/julia/062-cubic_permutations.jl b/julia/062-cubic_permutations.jl
new file mode 100644
index 0000000..08c07fc
--- /dev/null
+++ b/julia/062-cubic_permutations.jl
@@ -0,0 +1,32 @@
+###
+# Cubic permutations
+# Problem 62
+#
+# The cube, 41063625 (345^3), can be permuted to produce two other cubes: 56623104 (384^3)
+# and 66430125 (405^3). In fact, 41063625 is the smallest cube which has exactly three
+# permutations of its digits which are also cube.
+# Find the smallest cube for which exactly five permutations of its digits are cube.
+###
+
+
+using Base.Iterators
+
+cache = Dict()
+
+const PERMUTATIONS_COUNT = 5
+
+for n in countfrom(2)
+    cube = n ^ 3
+    key = sort(collect(string(cube)))
+    if !haskey(cache, key)
+        cache[key] = [cube]
+    else
+        push!(cache[key], cube)
+    end
+    for v in values(cache)
+        if length(v) == PERMUTATIONS_COUNT
+            println(minimum(v))
+            exit(0)
+        end
+    end
+end