列如c<<=2就 c=c<<2把c右移2位取到的值 给 c再如 a = 2c<<=a + 3+ 的属性比<<=高即c = c<<(a+3)即c = c<< 5C语言运算符属性 祥细索引http://www.slyar.com/blog/c-operator-priority.html
位算术。。操作系统都是8进制的嘛~靠左边有俩向下