> 3
> YNYYYYN  this line could possiblly be 6 with the g segment is broken;
> YNYYNYN  this line could possiblly be 5;
> NYYNYYN  this line could possiblly be 0 wiht the a and d segment are broken additionally;
> and 6 5 0 is a valid count down sequence.
请注意!!!!!
6 5 0 不是合法的记数序列。所以MISMATCH。
合法的记数序列应该是6 5 4。
这你可以倒数试试。