In this task your given two statements in Chinese. You must judge whether the second sentence is the cause or effect of the first one. Label the instances as "cause" or "effect" based on your judgment. The sentences are separated by a newline character.

司机的轮胎瘪了。
他压过了一个钉子。
cause

旅客到达边境。
巡逻员检查了他们的护照。
effect

我在锁上输入了我的组合密码。
锁开了。

effect