【进阶实战】Lua权重抽取：祖玛教主战利的组队权重分摊

local function pick(actor, ws)
    local r = math.random(1, ws[1] + ws[2] + ws[3])
    if r <= ws[2] then return 2 end    -- 边界错位，1号区间被跳过
    if r <= ws[1] then return 1 end
    return 3
end

local function pick(actor, ws)
    local sum = 0
    for i = 1, #ws do sum = sum + ws[i] end
    local r = math.random(1, sum)
    local acc = 0
    for i = 1, #ws do
        acc = acc + ws[i]
        if r <= acc then return i end  -- 累计区间与权重一一对应
    end
end
sendmsg(actor, 1, "祖玛教主战利归属 "
    .. pick(actor, {5000, 3000, 2000}) .. " 号队员")