fisher_yates_shuffe algorithm

Fisher_Yates_ShuffArr.lua

--Fisher_Yates_Shuff随机算法 
local function shuffarray_fisher_yates(num)
    local rand_seq = {}
    for i = num, 1, -1 do
        local idx = math.random(i)
        local temp = rand_seq[i] or i
        rand_seq[i] = (rand_seq[idx] or idx)
        rand_seq[idx] = temp
    end
    return rand_seq
end