使用 Python 代码实现多线程求合数的个数。

你好，针对您的问题，以下是 Python 代码实现多线程求合数的个数的示例：

import threading

# 判断一个数是否为合数
def is_composite(n):
    if n < 2:
        return False
    for i in range(2, int(n ** 0.5) + 1):
        if n % i == 0:
            return True
    return False

# 多线程求合数的个数
def count_composite_numbers(start, end, count):
    for i in range(start, end):
        if is_composite(i):
            count += 1
    return count

if __name__ == '__main__':
    num_threads = 4
    num_range = 1000000
    count = 0
    threads = []
    # 创建多个线程
    for i in range(num_threads):
        start = int(i * num_range / num_threads)
        end = int((i + 1) * num_range / num_threads)
        thread = threading.Thread(target=count_composite_numbers, args=(start, end, count))
        threads.append(thread)
    # 启动所有线程
    for thread in threads:
        thread.start()
    # 等待所有线程执行完毕
    for thread in threads:
        thread.join()
    print("合数的个数为:", count)

希望对您有所帮助！如果您有更多问题，欢迎继续提问。