http://www.cnblogs.com/kriss/archive/2005/10/24/261131.html http://www.cnblogs.com/cpcpc/archive/2011/01/17/2123086.html
http://www.cnblogs.com/kriss/archive/2005/10/24/261131.html
http://www.cnblogs.com/cpcpc/archive/2011/01/17/2123086.html