Lua布谷鸟哈希：双桶占位的迁巢策略

local t1, t2 = {}, {}
local function h1(k) return k % 7 + 1 end
local function h2(k) return (k * 5 + 3) % 7 + 1 end

local function cuckooInsert(key, val)
    for _ = 1, 8 do
        if t1[h1(key)] == nil then
            t1[h1(key)] = {key, val}
            return true
        end
        if t2[h2(key)] == nil then
            t2[h2(key)] = {key, val}
            return true
        end
        local old = t1[h1(key)]
        t1[h1(key)] = {key, val}
        key, val = old[1], old[2]
    end
    return false   -- 反复迁巢失败
end
local function lookup(key)
    local e = t1[h1(key)] or t2[h2(key)]
    return e and e[1] == key and e[2] or nil
end
local p = getplayerbyname("cuckoo01")
cuckooInsert(101, "jia")
cuckooInsert(108, "yi")
sendmsg(p, 1, tostring(lookup(101)) .. " "
    .. tostring(lookup(108)))