若有宏定义:#define S(a,b) t=a;a=b;b=t由于变量t没定义,所以此宏定义...答:宏就是符号定义,宏扩展时只是字符串替换,所以这个宏是正确的,也能正常使用。include "stdio.h"define s(a,b) t=a;a=b;b=t int main(int argv,char *argc[]){ int x=4,y=123,t;printf("x = %d\ty = %d\n",x,y);s(x,y);printf("x = %d\ty = %d\n",x,y);return ...