模拟实现动态分区分配中首次适应算法、循环首次适应算法、最佳适应算法和最坏适应算法。

以下是模拟实现动态分区分配中四种算法的Python代码：

1. 首次适应算法

def first_fit(memory_blocks, process_size):
    for i in range(len(memory_blocks)):
        if memory_blocks[i] >= process_size:
            memory_blocks[i] -= process_size
            return True
    return False

2. 循环首次适应算法

def next_fit(memory_blocks, process_size, last_index):
    for i in range(last_index, len(memory_blocks)):
        if memory_blocks[i] >= process_size:
            memory_blocks[i] -= process_size
            return i
    for i in range(last_index):
        if memory_blocks[i] >= process_size:
            memory_blocks[i] -= process_size
            return i
    return -1

3. 最佳适应算法

def best_fit(memory_blocks, process_size):
    best_index = -1
    for i in range(len(memory_blocks)):
        if memory_blocks[i] >= process_size:
            if best_index == -1 or memory_blocks[i] < memory_blocks[best_index]:
                best_index = i
    if best_index != -1:
        memory_blocks[best_index] -= process_size
        return True
    return False

4. 最坏适应算法

def worst_fit(memory_blocks, process_size):
    worst_index = -1
    for i in range(len(memory_blocks)):
        if memory_blocks[i] >= process_size:
            if worst_index == -1 or memory_blocks[i] > memory_blocks[worst_index]:
                worst_index = i
    if worst_index != -1:
        memory_blocks[worst_index] -= process_size
        return True
    return False