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Toeplitz Matrix

Problem Statement​

Given an m x n matrix, return true if the matrix is Toeplitz. Otherwise, return false.

A matrix is Toeplitz if every diagonal from top-left to bottom-right has the same elements.

Leetcode Link

Example 1:​

ex1

Input: matrix = [[1,2,3,4],[5,1,2,3],[9,5,1,2]]
Output: true
Explanation:
In the above grid, the diagonals are:
"[9]", "[5, 5]", "[1, 1, 1]", "[2, 2, 2]", "[3, 3]", "[4]".
In each diagonal all elements are the same, so the answer is True.

Example 2:​

ex1

Input: matrix = [[1,2],[2,2]]
Output: false
Explanation:
The diagonal "[1, 2]" has different elements.

Constraints:​

  • m == matrix.length
  • n == matrix[i].length
  • 1 <= m, n <= 20
  • 0 <= matrix[i][j] <= 99

Code​

Python Code

class Solution:
    def isToeplitzMatrix(self, matrix: List[List[int]])->bool:
        r_len, c_len = len(matrix),len(matrix[0])

        for r in range (1, r_len):
            for c in range (1, c_len):
                if matrix[r][c]!=matrix[r-1][c-1]:
                    return False

        return True