输出后者，逗号表达式（a+b，a-b）值为a-b
int a=-10,b=-3;
printf("%d %d\n",( a+b) ,(a-b));
2012-07-24 20:50
2012-07-24 21:29
2012-07-24 23:56
2012-07-25 00:04
