You are not given n non-negative integers X0, X1, . . . , Xn−1 less than 220, but they do exist, and their values never change. I’ll gradually provide you some facts about them, and ask you some questions. There are two kinds of facts, plus one kind of question: Format Ipv I p q v Q k p1 p2 ...pk Meaning ItellyouXp =v I tell you Xp XOR Xq = v Please tell me the value of Xp1 XOR Xp2 XOR...XOR Xpk Input There will be at most 10 test cases. Each case begins with two integers n and Q (1 ≤ n ≤ 20, 000, 2 ≤ Q ≤ 40, 000). Each of the following lines contains either a fact or a question, formatted as stated above. The k parameter in the questions will be a positive integer not greater than 15, and the v parameter in the facts will be a non-negative integer less than 220. The last case is followed by n = Q = 0, which should not be processed. Output For each test case, print the case number on its own line, then the answers, one on each one. If you can’t deduce the answer for a particular question, from the facts I provide you before that question, print ‘I don't know.’, without quotes. If the i-th fact (don’t count questions) cannot be consistent with all the facts before that, print ‘The first i facts are conflicting.’, then keep silence for everything after that (including facts and questions). Print a blank line after the output of each test case. Sample Input 26 I013 Q10 Q210 I02 Q11 Q10 33 I016 I022 Q212 24 I017 Q201 I018 Q201 00
2/2 Sample Output Case 1: I don't know. 3 1 2 Case 2: 4 Case 3: 7 The first 2 facts are conflicting.