Calculate the running time, using Big-O notation, of the following implementation of the greedy algorithm for the interval scheduling problem.

Intreval-Scheduling

% R - Array of n requests ;

Sort-by-Finish-Time(R) ;

A <-- {R[0]};

currentReq <-- R[0];

k <-- 1 ;

while k < n do

if currentReq.finishTime <= R[k].startTime then

A <-- A U(union) {R[k]}

currentReq <-- R[k]

end

k++

end