Given a number N, your task is to complete the function which generates all n-bit grey code sequences, a grey code sequence is a sequence such that successive patterns in it differ by one bit.
The first line of input contains an integer T denoting the no of test cases. Then T test cases follow. Each test case contains an integer N.
For each test case in print the generated grey code sequences separated by space.
Example(To be used for expected output):
00 01 11 10