totally confused

I just tested
int a=10
printf("a=%d a++=%d ++a=%d",a, a++,++a);

The gcc's output is:
a=12 a++=10 ++a=12
How to explain this? No matter which direction, the arguments are pushed into the stack, this result is not reasonable.

所有跟帖： 

• 3! anwsers. Avoid! -紅辣椒- ♀ (13 bytes) () 06/30/2004 postreply 17:23:18

• 能解釋嗎? -真糊塗啦啦...- ♀ (0 bytes) () 06/30/2004 postreply 19:38:44

• 回複：能解釋嗎? -紅辣椒- ♀ (317 bytes) () 06/30/2004 postreply 19:47:15

• 這樣看來,還是VC++合理些 -意味深長- ♀ (0 bytes) () 06/30/2004 postreply 19:46:01

• Finally! got the answer, -fianlly- ♀ (81 bytes) () 07/01/2004 postreply 08:43:49