【入门夯实】Lua补值查找：仓库双材料凑价配对裁决之杖

local function pair(items, target)
    for i = 1, #items do
        for j = i + 1, #items do   -- 双循环平方级，500项12万次
            if items[i] + items[j] == target then
                return items[i], items[j]
            end
        end
    end
end

local function pair(items, target)
    local seen = {}
    for _, v in ipairs(items) do
        local need = target - v
        if seen[need] then
            return need, v         -- 补值已见，配对成功
        end
        seen[v] = true
    end
end
local a, b = pair({8000, 7001, 15001, 7000}, 15001)
sendmsg(actor, 1, "凑价配对 " .. a .. " 与 " .. b
    .. " 合成裁决之杖")