Leetcode 74. Search a 2D Matrix

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 from left to right.
The first integer of each row is greater than the last integer of the previous row.
Example 1:

Input:
matrix = [
  [1,   3,  5,  7],
  [10, 11, 16, 20],
  [23, 30, 34, 50]
]
target = 3
Output: true
Example 2:

Input:
matrix = [
  [1,   3,  5,  7],
  [10, 11, 16, 20],
  [23, 30, 34, 50]
]
target = 13
Output: false

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

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