O(nlogn) is the bound for a serial version of the algorithm. A head that can read or write one value (stick) at a time. Parallel sorts achieve better bounds.

O(nlogn) is the bound for a serial version of the algorithm. A head that can read or write one value (stick) at a time. Parallel sorts achieve better bounds. Your sticky horizontal plate is essentially N parallel reads, each scanning through values, continually asking if it's reached its stick.