小中大http://wenku.baidu.com/link?url=EilBW4cMXRG_aaAKSfNolCW12PMg8oIx8hCfBV-1MLfmGue7uMZRxo-MPEGTFocj9nyeA6YVfmZc6Y1B2hzV23zlwCwlmxAWCUr9rrWFJ1m
cuturl('http://wenku.baidu.com/link?url=OJGXSgZuOw8RvwnVZ6rCIdwnBLMdF9sGTyy7-Raok48AFqbMBYCXM0Hl4wW1pvwQSc0qGOi6yXbDSs1LQRF8xb12fcQKeLIk4-cvbUA7Wr_')
cuturl('http://wenku.baidu.com/link?url=OJGXSgZuOw8RvwnVZ6rCIdwnBLMdF9sGTyy7-Raok48AFqbMBYCXM0Hl4wW1pvwQKAIG1FJlGBuANQKCqLKs7_tupvkV2dSrnwbfeNtMY6e')
百度就可以。