题目描述
<p></p> <h2>Problem B: Octagons</h2> <p>Below is a picture of an infinite hyperbolic tessellation of octagons. If we think of this as a graph of vertices (of degree three), then there exists an isomorphism of the graph which maps any vertex <i>x</i> onto any other vertex <i>y</i>. Every edge is given a label from the set <i>{a,b,c}</i> in such a way that every vertex has all three types of edges incident on it, and the labels alternate around each octagon. Part of this labeling is illustrated in the diagram.</p> <p><img src="http://tk.hustoj.com/admin/../upload/pimg28250_1.png" alt="" /></p> <p>So a path in this graph (starting from any vertex) can be specified by a sequence of edge labels. Your job is to write a program which, given a squence of labels such as "abcbcbcabcaccabb", returns "closed" if the path ends on the same vertex where it starts, and returns "open" otherwise.</p>
输入格式
<p>The input will begin with a number <i>Z</i> ≤ 200 on a line by itself. This is followed by <i>Z</i> lines, each of which is a squence of length at least 1 and at most 40 of 'a's 'b's and 'c's.</p>
输出格式
<p>For each input instance, the output will be the words "closed" or "open", each on a single line.</p>
样例
样例输入 1
2
abababab
abcbcbcbcba
样例输出 1
closed
open
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