全ての部分集合をbit全探索で求める

やりたいこと

2 4 1 4 2

上記の数列に対して、全ての部分集合を求めます。

ソースコード

ary = [2, 4, 1, 4, 2]
n = size(ary, 1)

# 1<<nは、2^5と同じ意味である。
for bit ∈ 0:(1<<n)-1
    s = []

    for i ∈ 0:length(ary)-1
        if bit & 1 << i ≠ 0
            push!(s, ary[i+1])
        end
    end

    @show s
end

出力結果

s = Any[]
s = Any[2]
s = Any[4]
s = Any[2, 4]
s = Any[1]
s = Any[2, 1]
s = Any[4, 1]
s = Any[2, 4, 1]
s = Any[4]
s = Any[2, 4]
s = Any[4, 4]
s = Any[2, 4, 4]
s = Any[1, 4]
s = Any[2, 1, 4]
s = Any[4, 1, 4]
s = Any[2, 4, 1, 4]
s = Any[2]
s = Any[2, 2]
s = Any[4, 2]
s = Any[2, 4, 2]
s = Any[1, 2]
s = Any[2, 1, 2]
s = Any[4, 1, 2]
s = Any[2, 4, 1, 2]
s = Any[4, 2]
s = Any[2, 4, 2]
s = Any[4, 4, 2]
s = Any[2, 4, 4, 2]
s = Any[1, 4, 2]
s = Any[2, 1, 4, 2]
s = Any[4, 1, 4, 2]
s = Any[2, 4, 1, 4, 2]

以上となります。