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Restore Sequence codechef november long challenge problem solution

 Restore Sequence codechef  november  long challenge  problem solution -

Restore Sequence codechef  november  long challenge  problem solution  lets read problem statement.

Alice has a very complex machine ― when fed with a sequence A1,A2,,AN, it produces a sequence B1,B2,,BN, where for each valid iBi is the largest index j such that Ai divides Aj (since Ai divides itself, such an index always exist). For example, if the machine is fed with A=[2,6,5,3,4], it produces B=[5,2,3,4,5].

Alice gave you a sequence B that was produced by the machine. Find an integer sequence A such that when it is fed into the machine, then the machine produces the sequence B. Alice does not like huge integers, so make sure that 1Ai4106 holds for each valid i.


  • The first line of the input contains a single integer T denoting the number of test cases. The description of T test cases follows.
  • The first line of each test case contains a single integer N.
  • The second line contains N space-separated integers B1,B2,,BN.


For each test case, print a single line containing N space-separated integers A1,A2,,AN. For each valid i1Ai4106 should hold.

If there are multiple solutions, you may print any of them. It is guaranteed that at least one solution exists.


  • 1T2104
  • 1N105
  • 1BiN for each valid i
  • the sum of N over all test cases does not exceed 2105


Subtask #1 (20 points): B1,B2,,BN are pairwise distinct

Subtask #2 (80 points): original constraints

Example Input

5 2 3 4 5
4 4 4 4

Example Output

2 6 5 3 4
2 6 3 12
Restore Sequence codechef  november  long challenge  problem solution


Restore Sequence codechef Solution -

It's necessary that b[i]>=i
let's assume my final ans is 2*n,2n-1,2n-2,2n-3...........n+1
I choose this initial sequence because ith element of this sequence cannot divide any other incoming element of this sequence.
store this sequence into a final answer vector
Now you have to change this sequence in such a way it can produce given B.
Now start iterating given array B.
Now change final ans like this
int k=v[i];

Finally, print ans vector.
Follow the code below.
This question can be done by another approach. 

Must Join Telegram channel for Editorial -

My code-


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