Lua二叉堆：建堆上浮下沉的完整实现

-- 错误：每次取最值全表排序，任务池越大越亏
table.sort(pool, function(a, b)
    return a.pri < b.pri
end)
return table.remove(pool, 1)

local heap = {}
local function sink(i)
    local n = #heap
    while i * 2 <= n do
        local m = i * 2
        if m + 1 <= n and heap[m + 1] < heap[m] then
            m = m + 1
        end
        if heap[m] >= heap[i] then break end
        heap[i], heap[m] = heap[m], heap[i]
        i = m
    end
end
local function push(v)
    heap[#heap + 1] = v
    local i = #heap
    while i > 1 and heap[math.floor(i / 2)] > heap[i] do
        local p = math.floor(i / 2)
        heap[p], heap[i] = heap[i], heap[p]
        i = p
    end
end
local function pop()
    local top = heap[1]
    local last = table.remove(heap)
    if #heap > 0 then
        heap[1] = last
        sink(1)
    end
    return top
end
local function build(arr)
    heap = arr
    for i = math.floor(#heap / 2), 1, -1 do
        sink(i)
    end
end
build({9, 4, 7, 1, 8, 2})
local label = panel:getChildByName("heapText")
label:setString(tostring(pop() == 1) .. "/" .. tostring(pop() == 2))