Sliding Window Counter

Problem

Simulate a sliding-window rate counter.

window_size is the window length and operations contains "hit" (record a hit at timestamps[i]) or "count" (return the hits with timestamps in (t - window_size, t]). Unlike a fixed window, the boundary moves with every query.

Return the list of recorded results (None for hit, an integer for count).

Hint

The window is open on the left and closed on the right: t - window_size < x <= t.

Test cases

case 1

in: [10,["hit","hit","hit","count","count"],[1,2,11,12,25]]

expected: [null,null,null,1,0]

case 2

in: [5,["hit","hit","count"],[1,6,6]]

expected: [null,null,1]

case 3

in: [5,["count"],[0]]

expected: [0]

case 4

in: [3,["hit","count"],[4,4]]

expected: [null,1]

Starter codePython

def sliding_window_counter(window_size, operations, timestamps):
    # Your code here
    pass

4 test cases · run your code against them in the editor