理论计算机科学 可计算性与计算复杂性 释文 NP-hard problem NP困难问题
- lubricating oil
- lubricating oil additive
- lubricating oil component
- lubricating oil system
- lubricating system
- lubrication
- lubrication equation
- lubrication in plastic working
- lubrication system
- lubrication theory
- lubricaton regime
- lubricator
- lubricity
- Lubug
- lubuge hydropower station
- Lubumbashi
- Lu Bɑn
- Luca Giordano
- Lu Cai
- lucalox
- Luca Marenzio
- Lu Can
- Lu Canal
- lucaogou formation tight oil
- Lucas