Leetcode 240. Search a 2D Matrix II

Seawolf

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:

Integers in each row are sorted in ascending from left to right.
Integers in each column are sorted in ascending from top to bottom.
Example:

Consider the following matrix:

[
  [1,   4,  7, 11, 15],
  [2,   5,  8, 12, 19],
  [3,   6,  9, 16, 22],
  [10, 13, 14, 17, 24],
  [18, 21, 23, 26, 30]
]
Given target = 5, return true.

Given target = 20, return false.

class Solution:
    def searchMatrix(self, matrix, target):
        """
        :type matrix: List[List[int]]
        :type target: int
        :rtype: bool
        """
        if matrix == None or len(matrix) == 0 or len(matrix[0]) == 0:
            return False
        
        row, col = 0, len(matrix[0]) - 1
        while row < len(matrix) and col >= 0:
            curt = matrix[row][col]
            
            if curt < target:
                row +=1
            elif curt > target:
                col -= 1
            else:
                return True
        return False