package q735

func asteroidCollision(asteroids []int) []int {
	p := 0
	for _, a := range asteroids {
		if a < 0 {
			for p > 0 && asteroids[p-1] > 0 && asteroids[p-1] < -a {
				p--
			}
			if p > 0 && asteroids[p-1] > 0 {
				if asteroids[p-1] == -a {
					p--
				}
				continue // explode
			}
		}
		asteroids[p] = a
		p++
	}
	return asteroids[:p]
}

var _ = asteroidCollision