scores = [9.0, 0.2, 4.0, 0.1, 0.3, 6.0, 0.2, 0.4, 0.1, 0.2]
budget = 6
recent_count = 2

positions = list(range(len(scores)))
recent = positions[-recent_count:]
older = positions[:-recent_count]

heavy_hitter_count = budget - recent_count
heavy_hitters = sorted(
    older,
    key=lambda position: scores[position],
    reverse=True,
)[:heavy_hitter_count]

retained = sorted(heavy_hitters + recent)

print("heavy hitters:", sorted(heavy_hitters))
print("recent positions:", recent)
print("retained positions:", retained)
print("cache entries:", len(retained), "of", len(scores))

# Output:
"""
heavy hitters: [0, 2, 5, 7]
recent positions: [8, 9]
retained positions: [0, 2, 5, 7, 8, 9]
cache entries: 6 of 10
"""