Which is the time complexity of the following Turing machine 

M = “On input string w of length n:

1. Scan across the tape and reject if a 0 is found to the right of a 1.

2. Repeat as long as some 0s and some 1s remain on the tape:

3. Scan across the tape, checking whether the total number of

   0s and 1s remaining is even or odd. If it is odd, reject.

4. Scan again across the tape, crossing off every other 0 starting with the first 0, and then crossing off every other 1 starting

   with the first 1.

5. If no 0s and no 1s remain on the tape, accept. Otherwise,

   reject .”