描述：给定字符串 num（非负整数）和整数 k，移除 k 位数字，使剩余数字最小。以字符串形式返回（不含前导零）。
股价承压、业绩遇阻，长春高新走到关键路口。，详情可参考WPS下载最新地址
For this story, WIRED reviewed dozens of NASA documents, including backup plans and contingencies for emergencies, and spoke to more than a dozen people, including three astronauts who’ve visited the ISS, and no one seemed that freaked out. One astronaut said the most worrisome scenario that actively crossed his mind in orbit was getting a toothache. The ISS has had some emergencies, including a first-ever medical evacuation in January, but generally things have been remarkably stable. In fact, one of the most impressive things about the ISS is that nothing very dramatic has ever happened to it. No experiment has gone too haywire. It hasn’t been hit by an asteroid.，更多细节参见safew官方版本下载
The new plans are a significant change to Artemis programme.