You are given a 2D binary matrix arr[][] filled with 0's and 1's. The array contains a square of 1's. So, you need to find that square and return its area.

Example 1

Input: 
1 1 1 1 0
1 1 1 1 1
1 1 1 1 1
1 0 1 0 0

Output: 9
Explanation: The largest square in the given matrix has an area of 9 sq. units.

Example 2

Input: 
0  0  0  0  1  1
0  1  1  1  1  0
0  1  1  1  1  0
0  1  1  1  1  0
1  1  1  1  1  1
1  0  0  0  0  0
Output: 16
Explanation: The largest square in the given matrix has an area of 16 sq. units.