735. Asteroid Collision 

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class Solution {
    public int[] asteroidCollision(int[] asteroids) {
        Stack<Integer> stack = new Stack<>();
        for (int asteroid : asteroids) {
            boolean bump = false;
            while (asteroid < 0 && !stack.isEmpty() && stack.peek() > 0) {
                // 此时发生碰撞
                if (-asteroid == stack.peek()) {
                    // 值相同，两个同时消失
                    bump = true;
                    stack.pop();
                    break;
                } else {
                    // 值不同，较小值消失
                    if (-asteroid < stack.peek()) {
                        bump = true;
                        break;
                    } else {
                        stack.pop();
                    }
                }
            }

            if (!bump) {
                stack.push(asteroid);
            }
        }

        int[] res = new int[stack.size()];
        for (int i = 0; i < res.length; i++) {
            res[res.length - 1 - i] = stack.pop();
        }
        return res;
    }
}

References

735. Asteroid Collision
剑指 Offer II 037. 小行星碰撞