C位运算中 异或运算符的 几点注意与示例

C语言的 异或运算的 运算原理 应用。需要注意的是 位运算 是符合 交换律, 结合律 及 分配律的

/* * ==================================================================== *           All Rights Reserved 2007-2015 CODD Orgnization * ==================================================================== * Title: xor.c * Desp: sample of bit xor operation  * Author: Liu Dongguo([e-mail]) * Verion: 1.0 * Created: 03/24/2015 22:09:14 PM * ChgOn: 2015-03-25 01:06:45 * ==================================================================== */////Principles////P0  x^x=0////P1  a^0=a////P2  c=a^x ==> a=c^x (=a^x^x=a^0=a)#include <stdio.h> int main (int argc, char* argv[]){////sample1 :swap two values int a=3;int b=517;printf("before swap:a=%d,b=%d\n",a,b);a^=b^=a^=b;printf("after swap:a=%d,b=%d\n",a,b);////samplp2: letter lowercase --> UPPERCASEint cMask='a'^'A';char c='b';printf("%c-->%c\n",c,c^cMask);////sample3: test Law of distributionif(12^22==(12^19+12^3)){printf("yes,xor obey Law of distribution\n");}return 0;}