R4-二分查找专题

直接二维变一维，然后二分查找就可以了

class Solution:
    def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:
        nums=[i for row in matrix for i in row]
        def binfind(the,target):
            low,high=0,len(the)-1
            while low<=high:
                  mid=(low+high)//2
                  if the[mid]==target:
                       return True
                  elif the[mid]>target:
                       high=mid-1
                  else:
                       low=mid+1
            return False
        return binfind(nums,target)