Data commit

Task/Combinations/Julia/combinations-1.julia

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+using Combinatorics
+n = 4
+m = 3
+for i in combinations(0:n,m)
+    println(i')
+end

Task/Combinations/Julia/combinations-2.julia

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+##############################
+# COMBINATIONS OF 3 OUT OF 5 #
+##############################
+
+# Set n and m
+m = 5
+n = 3
+
+# Prepare the boundary of the calculation. Only m - n numbers are changing in each position.
+max_n = m - n
+
+#Prepare an array for result
+result = zeros(Int64, n)
+
+function combinations(pos, val)            # n, max_n and result are visible in the function
+    for i = val:max_n                      # from current value to the boundary
+        result[pos] = pos + i              # fill the position of result
+        if pos < n                         # if combination isn't complete,
+           combinations(pos+1, i)         # go to the next position
+        else
+            println(result)                # combination is complete, print it
+        end
+   end
+end
+
+combinations(1, 0)
+end

Task/Combinations/Julia/combinations-3.julia

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+using Base.Iterators
+
+function bitmask(u, max_size)
+    res = BitArray(undef, max_size)
+    res.chunks[1] = u%UInt64
+    res
+end
+
+function combinations(input_collection::Vector{T}, choice_size::Int)::Vector{Vector{T}} where T
+    num_elements = length(input_collection)
+    size_filter(x) = Iterators.filter(y -> count_ones(y) == choice_size, x)
+    bitmask_map(x) = Iterators.map(y -> bitmask(y, num_elements), x)
+    getindex_map(x) = Iterators.map(y -> input_collection[y], x)
+
+    UnitRange(0, (2^num_elements)-1) |>
+        size_filter  |>
+        bitmask_map  |>
+        getindex_map |>
+        collect
+end