麻将胡牌，听牌算法

算法分析参照下面的ｂｌｏｇ麻将胡牌算法

我用lua写了一个简化的麻将算法，只考虑麻将字牌和万

牌编号1~9对应１－９万，１０－16是字牌

下面是lua代码

local print = print
local tconcat = table.concat
local tinsert = table.insert
local srep = string.rep
local type = type
local pairs = pairs
local tostring = tostring
local next = next

function print_r(root)
    local cache = {  [root] = "." }
    local function _dump(t,space,name)
        local temp = {}
        for k,v in pairs(t) do
            local key = tostring(k)
            if cache[v] then
                tinsert(temp,"+" .. key .. " {" .. cache[v].."}")
            elseif type(v) == "table" then
                local new_key = name .. "." .. key
                cache[v] = new_key
                tinsert(temp,"+" .. key .. _dump(v,space .. (next(t,k) and "|" or " " ).. srep(" ",#key),new_key))
            else
                tinsert(temp,"+" .. key .. " [" .. tostring(v).."]")
            end
        end
        return tconcat(temp,"\n"..space)
    end
    print(_dump(root, "",""))
end

local Hu = {}

function analyze(cards, zi)
    print_r(cards)
    print("zi", zi)
    if not next(cards) then
        return true
    end
    local start
    local over
    if zi then
        start = 10
        over = 16
    else
        start = 1
        over = 9
    end
    local finish = true
    for i = start, over do
        if cards[i] and cards[i] ~= 0 then
            start = i
            finish = false
            break
        end
    end
    if finish then -- 手牌为空
        return true
    end
    print("start", start)
    local result
    if cards[start] and cards[start] >= 3 then -- 刻牌
        cards[start] = cards[start] - 3
        result = analyze(cards , zi)
        cards[start] = cards[start] + 3
        return result
    end
    if not zi and cards[start +1] and cards[start + 2] and cards[start + 1] > 0 and cards[start + 2] > 0 then
        cards[start ] = cards[start ] - 1
        cards[start + 1] = cards[start + 1] - 1
        cards[start + 2] = cards[start + 2] - 1
        result = analyze(cards, zi)
        cards[start ] = cards[start ] + 1
        cards[start + 1] = cards[start + 1] + 1
        cards[start + 2] = cards[start + 2] + 1
        return result
    end
    return false
end

function fmod( arr, num)
    local count = 0
    for k, v in pairs(arr) do
        count = count + v
    end
    return count % num
end

--是否可胡牌
function Hu:win( cards)
    local jiangPos
    local yuShu
    local jiangExisted = false
    local wan = {}
    local zi = {}
    for k, v in pairs(cards) do
        if k < 10 then
            wan[k] = v
        else
            zi[k] = v
        end
    end
    -- wan
    yuShu = fmod(wan, 3)
    if yuShu == 1 then
        return false
    elseif yuShu == 2 then
        jiangPos = wan
        jiangExisted = true
    end
    --zi
    yuShu = fmod(zi, 3)
    if yuShu == 1 then
        return false
    elseif yuShu == 2  then
        if jiangExisted then
            return false
        else
            jiangPos = zi
        end
    end

    if jiangPos == wan then
       if not analyze(zi, true) then
            return false
        end
    elseif not analyze(wan, false) then
        return false
    end
    if not jiangPos then -- no jiang
        return false
    end
    -- jiang
    local success = false
    for k, v in pairs(jiangPos) do
        if v >= 2 then
            jiangPos[k] = v - 2
            if analyze(jiangPos, jiangPos == zi) then
                success = true
            end
            jiangPos[k] = v
            if success then
                break
            end
        end
    end
    return success
end

--怎么听牌
function Hu:ting(cards)
    local success = false
    local post = {}
    local will = {}
    for k ,v in pairs(cards) do
        if v > 0 then
            cards[k] = cards[k] - 1
            print_r(cards)
            local willCards = {}
            for i = 1, 16 do
                if i ~= k then
                    if cards[i] then
                        cards[i] = cards[i] + 1
                    else
                        cards[i] = 1
                    end
                    success = self:win(cards)
                    cards[i] = cards[i] - 1
                    if success then
                        table.insert(willCards, i)
                    end
                end
            end
            cards[k] = cards[k] + 1
            if next(willCards) then
                will[k] = willCards
            end
        end
    end
    return will
end

local player = {
    [1]    = 1,
    [2] = 1,
    [3] = 1,
    [4] = 3,

    [10] = 3,
    [12] = 1,
    [13] = 1,
}
print_r(Hu:ting(player))
return Hu