def asteroid_collision(asteroids):
    stack = []
    for asteroid in asteroids:
        alive = True
        while alive and asteroid < 0 and stack and stack[-1] > 0:
            if stack[-1] < -asteroid:
                stack.pop()
            elif stack[-1] == -asteroid:
                stack.pop()
                alive = False
            else:
                alive = False
        if alive:
            stack.append(asteroid)
    return stack