字符串函数以及宏定义

最小值、以及平方的宏定义实现，注意（）的使用

 1 #include <stdio.h>
 2 #include <string.h>
 3 
 4 #define MIN(a,b) (a)<(b)?(a):(b)
 5 #define SQRT(a) (a)*(a)
 6 
 7 int main(int argc, char **argv) {
 8     printf("Hello, World!\n");
 9     
10     int a = 10;
11     int b = 20;
12     
13     int min = MIN(a,b);
14     
15     printf("min = %d\n",min);
16     
17     int sqrt = SQRT(a);
18     printf("sqrt = %d\n",sqrt);
19     
20     char *c = "abc";
21     printf("c = %s\n",c);
22     
23     char *d;
24     memcpy(d,c,2);
25     printf("d = %s\n",d);
26     
27     return 0;
28     
29 }