What is the complexity class of the recurrence T(n)=2T(n/2)+O(n)T(n) = 2T(n/2) + O(n)T(n)=2T(n/2)+O(n)?
O(n)O(n)O(n)
O(nlogn)O(n \log n)O(nlogn)
O(n2)O(n^2)O(n2)
O(logn)O(\log n)O(logn)