Maximal Rectangle in Binary Matrix

Given a rows by cols binary matrix filled with `0`'s and `1`'s, find the largest rectangle containing only `1`'s and return its area. ### Constraints - `1 <= m, n <= 200` - `matrix[i][j]` is either `0` or `1`. ### Input Format First line contains two integers `m` and `n` representing rows and columns. Next `m` lines each contain `n` space-separated integers (`0` or `1`). ### Output Format Print a single integer representing the maximal rectangle area.