Power Sum solution codechef- You are given a sequence A of N integers such that every element is a non-negative power of 2. A sequence is called good if its sum is a non-negative power of 2. You would like to turn A into a good sequence. To achieve this, you can perform the following operation on A

Power Sum solution codechef

You are given a sequence AA of NN integers such that every element is a non-negative power of 22.

A sequence is called good if its sum is a non-negative power of 22. You would like to turn AA into a good sequence.

To achieve this, you can perform the following operation on AA:

  • Pick a non-empty subsequence of AA, pick a positive integer XX such that X230X≤230, and multiply every element of this subsequence by XX.

Find the minimum number of operations required to turn AA into a good sequence. Also, find one sequence of operations which does this. If there are multiple possible answers, you may find any of them.

Input Format

  • The first line of input contains a single integer TT, denoting the number of test cases. The description of TT test cases follows.
  • The first line of each test case contains a single integer NN.
  • The second line of each test case contains NN space-separated integers A1,A2,,ANA1,A2,…,AN.

Output Format

For each test case, print the answer in the following format:

  • First, print one line containing an integer MM, denoting the minimum number of moves required.
  • Then, print 2M2M lines describing MM operations.
    • Each operation is described by 22 lines.
    • On the first line, print two space-separated integers KK and XX, denoting the size of the subsequence and the multiplier for this operation.
    • On the second line, print KK distinct space-separated integers denoting the indices of the elements chosen to be multiplied in this operation. These KK integers can be printed in any order.


  • 1T10001≤T≤1000
  • 1N1001≤N≤100
  • 1Ai2201≤Ai≤220


Subtask #1 (100 points): Original constraints

Sample Input 1 

4 8 4 32
2 2 4

Sample Output 1 

3 2
1 2 3


Test case 11: Multiplying the 1st,2nd1st,2nd and 3rd3rd elements by 22 turns the array into [8,16,8,32][8,16,8,32], whose sum is 64=2664=26.

Test case 22: The array is already good.

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