[数据结构与算法]java数据结构

一维数组:

对区间的合并

public class demo {
    public static void main(String[] args) {
       int [][] intervals = {{1,3},{2,6},{15,18},{8,10}};
        Solution solution = new Solution();
        int[][] merge = solution.merge(intervals);
        System.out.println("b:"+Arrays.deepToString(merge));

    }

    static class Solution {
        public int[][] merge(int[][] intervals) {
            if (intervals.length == 0) return intervals;
            //1、对二维数组按照第一列升序排序
            Arrays.sort(intervals, (a, b) -> a[0] - b[0]);
            //2、进行合并数组
            List<int []> list = new ArrayList<>();
            int term[] =intervals[0];//临时空间，1 判断是否需要合并集合，2 是否放入结果集
            System.out.println(Arrays.toString(term));
            for (int i = 1; i < intervals.length; i++) {
                if (term[1]>=intervals[i][0]){
                    term[1]=Math.max(term[1],intervals[i][1]);
                }else {
                    list.add(term);
                    term=intervals[i];
                }
            }
            list.add(term);
            return list.toArray(new int[list.size()][2]);
        }

    }
}