point covering number

例句：

1. 1. The point covering number is the minimum number of points required to cover a certain area.
   点覆盖数是覆盖一定面积所需的最少点数。
2. 2. In this case, the point covering number is 500.
   在这种情况下，点覆盖数是500。
3. 3. The point covering number can be used to determine the optimal coverage strategy for a given area.
   点覆盖数可以用来确定给定区域的最优覆盖策略。