题目是:某国为了防御敌国的导弹袭击，发展出一种导弹拦截系统。但是这种导弹拦截系统有一个缺陷：虽然它的第一发炮弹能够达到任意的高度，但是以后每一发炮弹都不能高于前一发的高度。某天，雷达捕捉到敌国的导弹来袭。由于该系统还在使用阶段，所以只有一套系统，因此有可能不能拦截所有的导弹。-topic is : a country in order to defend against enemy missile attacks, the development of a missile interception system. But such a missile interceptor system has a flaw : Although it's the first rounds to achieve highly arbitrary, but each shell and should not be higher than the former was too high. One day, the radar to capture incoming enemy missiles. As the system is still in use stage, only a system, it is not possible to intercept all missiles.