题解 | #合并区间#

import java.util.*;

/*
 * public class Interval {
 *   int start;
 *   int end;
 *   public Interval(int start, int end) {
 *     this.start = start;
 *     this.end = end;
 *   }
 * }
 */

public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param intervals Interval类ArrayList 
     * @return Interval类ArrayList
     */
    public ArrayList<Interval> merge (ArrayList<Interval>intervals ) {
        // write code here
         if(intervals.size()<=1){
                return intervals;
         }

         intervals.sort(Comparator.comparingInt(i->i.start));
           
        ArrayList<Interval> result = new ArrayList<>();//存放新的数据
        Interval current = intervals.get(0);
        for(int i=0;i<intervals.size();i++){
             if(intervals.get(i).start<=current.end){
               current.end = Math.max(intervals.get(i).end,current.end);
             }
               else{
                result.add(current);
                current = intervals.get(i);
               }
        }
          
        result.add(current);
        return result;

    }



}