一些简单的c语言处理技巧

摘录和整理一些简单的c处理技巧

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• 交换两个数的值 

1. 使用临时变量
2. 不适用临时变量

   int a = 1, b = 2;
   
   a = a + b; //a=1+2=3
   b = a - b; //b=3-2=1
   a = a - b; //a=3-1=2

    

3. 使用异或

   int a = 60; //0011 1100
   int b = 13; //0000 1101
   
   a = a ^ b; //a=a^b=0011 0001
   b = a ^ b; //b=a^b=0011 1100=60 
   a = a ^ b; //a=a^b=0000 1101=13 

    

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• 判断奇数/偶数

1. 判断除以2的余数是否为0

2. 与1做位相与 

   int number = 9; //十进制9的二进制表示为1001 
   
   if(number & 1)
   	printf("奇数\n");
   else
   	printf("偶数\n");
   

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   to be continued