TECHYIELD: Search a 2D Matrix II

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

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]
]

Using Search Space Reduction Method

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 not matrix:

return False

rows = len(matrix)

cols = len(matrix[0])

if rows == 0 or cols ==0:

return False

row = rows-1

col = 0

while row >=0 and col < cols:

if target == matrix[row][col]:

return True

elif target < matrix[row][col]:

row -= 1

else:

col+=1

return False

Time Complexity : O(m+n)

Space Complexity : O(1)

TECHYIELD