Lua循环节：除法余数的重复侦测

local function cycleLen(a, b)
    local seen, r, pos = {}, a % b, 0
    while r ~= 0 and seen[r] == nil do
        pos = pos + 1
        seen[r] = pos
        r = r * 10 % b
    end
    if r == 0 then return 0 end
    return pos - seen[r] + 1
end

local function cycleText(a, b)
    local seen, out = {}, {}
    local r = a % b
    while r ~= 0 and seen[r] == nil do
        seen[r] = #out + 1
        r = r * 10
        out[#out + 1] = math.floor(r / b)
        r = r % b
    end
    if r == 0 then return "有限小数" end
    return table.concat(out, "", seen[r])
end
local p = getplayerbyname("cyc01")
sendmsg(p, 1, "1/7 循环节 " .. cycleText(1, 7))