吐槽网上的题(http://www.devtucao.com/queryHistory/52d536b60cf2c0c1bf4043f4):
int a = Integer.MAX_VALUE;
int b = Integer.MAX_VALUE;
int sum = a + b;
System.out.println(sum);
参考一下补码的定义(http://www.cnblogs.com/zhangziqiu/archive/2011/03/30/ComputerCode.html),回过头来看懂了
e.g.
maxA = (0111)补 maxB = (0111)补
maxA+maxB = (1110)补 = (1010)原 = -2