byte: The byte data type is an 8-bit signed two’s complement integer. It has a minimum value of -128 and a maximum value of 127 (inclusive). The byte data type can be useful for saving memory in large arrays,where the memory savings actually matters. They can also be used in place of int where their limits help to clarify your code; the fact that a variable’s range is limited can serve as a form of documentation.
它如何节省内存？什么是2的赞美？
解决方法
从Wikipedia开始：
A two’s-complement system or two’s-complement arithmetic is a system in which negative numbers are represented by the two’s complement of the absolute value;07001 this system is the most common method of representing signed integers on computers.[2] In such a system,a number is negated (converted from positive to negative or vice versa) by computing its two’s complement. An N-bit two’s-complement numeral system can represent every integer in the range −2^(N−1) to +2^(N−1)−1.