Lua实战之拆分整数

Description

将指定的整数按规则由大到小拆分成多个更小的整数！

e.g.

被拆分的的整数：23

拆分规则：{1, 2, 3}

拆分结果：7个3，1个2

Implemention

function splitNum(targetNum, ruleTbl)
    if #ruleTbl == 0 then
        return targetNum
    end

    for i = #ruleTbl, 1, -1 do
        local count = math.modf(targetNum / ruleTbl[i])
        if count > 0 then
            print(ruleTbl[i], count)
            targetNum = targetNum % ruleTbl[i]
            if targetNum == 0 then
                break
            end
        end
    end
    if targetNum > 0 then
        print("split failed->", targetNum)
    end    
end

local targetNum = 23
local ruleTbl = {1, 2, 3}
splitNum(targetNum, ruleTbl)
-- 3	7
-- 2	1

Tips

浮点型的数由于精度问题，不能像整数这样拆分！但是可以先将浮点型的数转成整数进行拆分，再还原回去即可！