Virtual Memory Management: LRU, FIFO, and Clock Page Replacement Algorithms

# Second-Chance (Clock) Page Replacement Simulator
def clock_page_replacement(pages, capacity):
    memory = [-1] * capacity
    use_bit = [0] * capacity
    pointer = 0
    page_faults = 0

    for page in pages:
        if page in memory:
            idx = memory.index(page)
            use_bit[idx] = 1
        else:
            page_faults += 1
            while use_bit[pointer] == 1:
                use_bit[pointer] = 0
                pointer = (pointer + 1) % capacity
            memory[pointer] = page
            use_bit[pointer] = 1
            pointer = (pointer + 1) % capacity

    return page_faults

print("Page Faults:", clock_page_replacement([1, 2, 3, 4, 1, 2, 5, 1, 2, 3, 4, 5], 3))