maximal-rectangle

给定一个仅包含 0 和 1 、大小为 rows x cols 的二维二进制矩阵，找出只包含 1 的最大矩形，并返回其面积。

示例 1：

输入：matrix = [["1","0","1","0","0"],["1","0","1","1","1"],["1","1","1","1","1"],["1","0","0","1","0"]]
输出：6
解释：最大矩形如上图所示。

示例 2：

输入：matrix = [["0"]]
输出：0

示例 3：

输入：matrix = [["1"]]
输出：1

提示：

• rows == matrix.length


• cols == matrix[0].length


• 1 <= rows, cols <= 200


• matrix[i][j] 为 '0' 或 '1'