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.

1. class Solution:
   
2.     def searchMatrix(self, matrix, target):
   
3.         """
   
4.         :type matrix: List[List[int]]
   
5.         :type target: int
   
6.         :rtype: bool
   
7.         """
   
8.         if matrix == None or len(matrix) == 0 or len(matrix[0]) == 0:
   
9.             return False
   
10.         
    
11.         row, col = 0, len(matrix[0]) - 1
    
12.         while row < len(matrix) and col >= 0:
    
13.             curt = matrix[row][col]
    
14.             
    
15.             if curt < target:
    
16.                 row +=1
    
17.             elif curt > target:
    
18.                 col -= 1
    
19.             else:
    
20.                 return True
    
21.         return False

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