B'A way to make a new task is to make it nondeterministic or probabilistic. For example, the hard task of Topcoder SRM 595, Constellation, is the probabilistic version of a convex hull. Let 's try to make a new task. Firstly we will use the following task. There are n people, sort them by their name. It is just an ordinary sorting problem, but we can make it more interesting by adding nondeterministic element. There are n people, each person will use either his/her first name or last name as a handle. Can the lexicographical order of the handles be exactly equal to the given permutation p? More formally, if we denote the handle of the i-th person as hi, then the following condition must hold: . The first line contains an integer n (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89105) -- the number of people. The next n lines each contains two strings. The i-th line contains strings fi and si (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89|fi|, xe2 x80 x89|si| xe2 x80 x89 xe2 x89 xa4 xe2 x80 x8950) -- the first name and last name of the i-th person. Each string consists only of lowercase English letters. All of the given 2n strings will be distinct. The next line contains n distinct integers: p1, xe2 x80 x89p2, xe2 x80 x89..., xe2 x80 x89pn (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89pi xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n). If it is possible, output "YES", otherwise output "NO". In example 1 and 2, we have 3 people: tourist, Petr and me (cgy4ever). You can see that whatever handle is chosen, I must be the first, then tourist and Petr must be the last. In example 3, if Copernicus uses "copernicus" as his handle, everything will be alright.'...