二叉树的应用举例：将设计一个算法以确定把信号放大器放在何处。目标是要使所用的放大器数目最少并且保证信号衰减(与源端信号相关)不超过给定的容忍值。-Binary Application examples: the design of an algorithm to determine where to put the signal amplifier. Goal is to make the minimum number of amplifiers used in signal attenuati