区间覆盖问题的算法实现 问题描述：给出x轴上N条线段的坐标，从中选出一些线段来覆盖区间【0，M】，要求所用线段数目最少 -Interval coverage of the realization of the algorithm descr iption: In this paper, x-axis N be the coordinates of line segment, selected to cover a number