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。-A country to defend against enemy missile attacks, to develop a missile interception system. But the missile defense system has a flaw: although it s the first rounds to reach any height, but later shells can not be higher than every before out of heights. One day, to capture enemy radar missile strikes. As the system is still using the stage, so only one system, so there may not be able to intercept all the missiles.