Count Every All-One Square in a Binary Matrix

### Problem Return the number of contiguous square submatrices of matrix whose entries are all 1. Count different positions and different side lengths separately. ```cpp class Solution { public: int countSquares(vector<vector<int>>& matrix); }; ``` ### Examples **Example 1:** ```text Input: matrix = [[1,1],[1,1]] Output: 5 Explanation: Four1-by-1 squares and one2-by-2 square are all ones. ``` **Example 2:** ```text Input: matrix = [[1,0,1]] Output: 2 Explanation: Only the two individual1 cells are qualifying squares. ``` ### Constraints - Each matrix dimension is between 1 and 300. - Every entry is 0 or 1. ### Contract considerations Count every qualifying position and side length separately. A nonsquare rectangular submatrix is not counted. ```hint Read the boundary condition Are different positions and side lengths counted separately, and do rectangular regions qualify? ``` ### Boundary reminders Count every qualifying position and side length separately. A nonsquare rectangular submatrix is not counted.