4位二进制并行加法器。现在普遍使用的并行加法器是超前进位加法器，在几个全加器的基础上增加了一个超前进位形成逻辑，以减少由于逐步进位信号的传递所造成的时延。-Four binary parallel adder. Now commonly used parallel adder is advanced in several adder, carries on the basis of QuanJia device adds an advanced form logic, to reduce car