You are given an m x n binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area.
Example 1:
Input: matrix = [
["1","0","1","0","0"],
["1","0","1","1","1"],
["1","1","1","1","1"],
["1","0","0","1","0"]
]
Output: 4Example 2:
Input: matrix = [
["0","1"],
["1","0"]
]
Output: 1Constraints:
1 <= matrix.length, matrix[i].length <= 300matrix[i][j] is '0' or '1'.