转载自:https://www.cnblogs.com/911/archive/2008/05/20/1203477.html

补充:"异或"运算
对于二进制整数a、b（如a=00011011,b=01000011)
a^a=0;
a^00000000=a;
c=a ^ b==>a=c ^ b=a ^ b ^ b=a ^ 0=a;