from typing import List
class Solution:
    
    def merge(self, intervals: List[List[int]]) -> List[List[int]]:
        intervals.sort()
        outp = []
        inlen =len(intervals)
        curli = intervals[0]
        if inlen == 1:
            return intervals
        else:
            for i in range(1,inlen):
                if intervals[i][0] > curli[1]:
                    outp.append(curli)
                    curli = intervals[i]
                    continue
                else:
                    if intervals[i][1] >curli[1]:
                        curli[1] = intervals[i][1]
            outp.append(curli)
            outp.sort()
            return outp