经典算法_位运算

 

1 按位异或

适用于：面试，嵌入式开发需要节约内存的场合

不借助中间变量，交换2个变量

有3种方法，1是相加，2是相乘，3是按位异或，其中按位异或最好，因为不会越界

 

 1 #define _CRT_SECURE_NO_WARNINGS
 2 
 3 #include<stdio.h>
 4 #include<stdlib.h>
 5 
 6 main()
 7 {
 8     int a = 100;
 9     int b = 10;
10     
11     int c = 200;
12     int d = 20;
13 
14     int e = 300;
15     int f = 30;
16 
17     printf("a=%d,b=%d\n", a, b);
18 
19     a = a + b;
20     b = a - b;
21     a = a - b;
22 
23     printf("a=%d,b=%d\n", a, b);
24 
25     printf("c=%d,d=%d\n", c, d);
26 
27     c = c*d;
28     d = c / d;
29     c = c / d;
30 
31     printf("c=%d,d=%d\n", c, d);
32 
33     printf("e=%d,f=%d\n", e, f);
34 
35     e = e^f;
36     f = e^f;
37     e = e^f;
38 
39     printf("e=%d,f=%d\n", e, f);
40 
41     system("pause");
42 }