Lua贪心选择：互斥区间的调度策略

-- 错误：按开始时间排序，长活动霸场
table.sort(list, function(a, b)
    return a[1] < b[1]
end)

local function pickMax(list)
    table.sort(list, function(a, b)
        return a[2] < b[2]
    end)
    local out, lastEnd = {}, -math.huge
    for _, it in ipairs(list) do
        if it[1] > lastEnd then
            out[#out + 1] = it
            lastEnd = it[2]
        end
    end
    return out
end