一、取反 ~
#include<stdio.h>
#include<stdlib.h> void main(){
unsigned char ch=; //0000 1111 char的单位是字节，1B=8bit，所以是8位
unsigned char fch=~ch; //1111 0000 取反
unsigned char ffch=~fch;//0000 1111 printf("%d,%d,%d\n",ch,fch,ffch);
system("pause");
}
注意：取反运算符不改变操作数的值，赋值运算符才会改变。
二、与运算 &
#include<stdio.h>
#include<stdlib.h> //位与 1,1->1 01,10,00->0
//1&0=0 , 0&0=0 ->清零
//1&1=1 ，0&1=0 ->保留某些位不变 void main0(){
unsigned char ch1=; //0000 0011
unsigned char ch2=; //1111 0000
unsigned char ch3=; //1111 1111 printf("%d\n",ch1&ch2); //0000 0000 0
printf("%d\n",ch1&ch3); //0000 0011 3
printf("%d\n",ch2&ch3); //1111 0000 240
system("pause");
} //位与实现按位清零
void main1(){
unsigned char ch1=; //1111 1111
unsigned char ch2=; //0000 1111
unsigned char ch3=; //1111 0000 printf("%d\n",ch1&ch2); //清零高四位
printf("%d\n",ch1&ch3); //清零低四位
printf("%d\n",ch1&); //全部清零
system("pause");
} //位与实现取出指定位
void main(){
unsigned char ch=; //1010 1001
unsigned char ch1=; //0011 1100
//0010 1000 40 printf("%d\n",ch&ch1); //取出中间四位
system("pause");
}
三、或运算 |
#include<stdio.h>
#include<stdlib.h> //位或运算 1|1=1 1|0=1 0|1=1 0|0=0
void main0(){
unsigned char ch=; //1010 1001
unsigned char ch1=; //1111 0000
//1111 1001 249
printf("%d\n",ch|ch1);
system("pause");
} //位或运算符可以让某些位变成1 1|0 = 1|1 =1
// 0|1=1 0|0=0 与0相或不改变
void main(){
unsigned char ch=; //1010 1001
unsigned char ch1=; //0000 1111
//1010 1111 实现低四位全部变1
printf("%d\n",ch|ch1);
system("pause");
}
四、异或运算 ^（相同为0，相异为1）
不借助中间变量，实现两变量交换值
#include<stdio.h>
#include<stdlib.h> //异或 1^1=0 1^0=1 0^1=1 0^0=0
void main0(){
unsigned char ch1=; //1010 1001
unsigned char ch2=; //0000 1111
//1010 0110 166
printf("%d\n",ch2^ch1);
system("pause");
} //异或可以实现反转
void main1(){
unsigned char ch1=; //1010 1001
unsigned char ch2=; //1111 1111 全部反转
//0101 0110 86
printf("%d\n",ch2^ch1);
system("pause");
}
void main2(){
unsigned char ch1=; //1010 1001
unsigned char ch2=; //0011 1100 指定位反转（中间反转）
//1001 0101 149
printf("%d\n",ch2^ch1);
system("pause");
}
//异或交换两个变量
//不借助中间变量，实现两个变量的交换——>面试和嵌入式开发
//x，y交换值 x=x^y;y=x^y;x=x^y
/*
等同于加减法实现交换值
x=20,y=10;
x=x+y; //x=30,y=10
y=x-y; //x=30,y=20
x=x-y; //x=10,y=20
*/
void main(){
unsigned char ch1=; //0001 0100
unsigned char ch2=; //0000 1010
printf("%d，%d\n",ch1,ch2); ch1=ch1^ch2;
ch2=ch1^ch2;
ch1=ch1^ch2; printf("交换之后%d，%d\n",ch1,ch2);
system("pause");
}
五、位运算总结
#include<stdio.h>
#include<stdlib.h> void main(){
unsigned char ch1=; //1010 1000
unsigned char ch2=; //1000 0101 printf("&与：%d\n",ch1&ch2); //1000 0000 128
printf("|或：%d\n",ch1|ch2); //1010 1101 173
printf("^异或：%d\n",ch1^ch2); //0010 1101 45
unsigned char ch3=~ch1,ch4=~ch2;
printf("~反：%d,%d %d,%d\n",ch3,ch4,~ch1,~ch2);
system("pause");
}
