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1363D · Guess The Maximums

2100 · binary search, implementation, interactive

Problem: This is an interactive problem.

Ayush devised a new scheme to set the password of his lock. The lock has kk slots where each slot can hold integers from 11 to nn. The password PP is a sequence of kk integers each in the range [1,n][1, n], ii-th element of which goes into the ii-th slot of the lock.

To set the password of his lock, Ayush comes up with an array AA of nn integers each in the range [1,n][1, n] (not necessarily distinct). He then picks kk non-empty mutually disjoint subsets of indices S1,S2,...,SkS_1, S_2, ..., S_k (SiijSj=)(S_i \underset{i \neq j} \cap S_j = \emptyset) and sets his password as Pi=maxjSiA[j]P_i = \max\limits_{j \notin S_i} A[j]. In other words, the ii-th integer in the password is equal to the maximum over all elements of AA whose indices do not belong to SiS_i.

You are given the subsets of indices chosen by Ayush. You need to guess the password. To make a query, you can choose a non-empty subset of indices of the array and ask the maximum of all elements of the array with index in this subset. You can ask no more than 12 queries.

Input Format: The first line of the input contains a single integer tt (1t10)(1 \leq t \leq 10) — the number of test cases. The description of the test cases follows.

The first line of each test case contains two integers nn and kk (2n1000,1kn)(2 \leq n \leq 1000, 1 \leq k \leq n) — the size of the array and the number of subsets. kk lines follow. The ii-th line contains an integer cc (1c<n)(1 \leq c \lt n) — the size of subset SiS_i, followed by cc distinct integers in the range [1,n][1, n]  — indices from the subset SiS_i.

It is guaranteed that the intersection of any two subsets is empty.

Note: The array AA in the example is [1,2,3,4][1, 2, 3, 4]. The length of the password is 22. The first element of the password is the maximum of A[2]A[2], A[4]A[4] (since the first subset contains indices 11 and 33, we take maximum over remaining indices). The second element of the password is the maximum of A[1]A[1], A[3]A[3] (since the second subset contains indices 22, 44).

Do not forget to read the string "Correct" / "Incorrect" after guessing the password.

Sample Cases

Case 1

Input

1
4 2
2 1 3
2 2 4

1

2

3

4

Correct

Output

? 1 1

? 1 2

? 1 3

? 1 4

! 4 3

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