[LeetCode] 221. 最大正方形

class Solution {
    public int maximalSquare(char[][] matrix) {
                if (matrix == null || matrix.length < 1 || matrix[0].length < 1) return 0;

        int height = matrix.length;
        int width = matrix[0].length;
        int maxSide = 0;
        int[][] dp = new int[height + 1][width + 1];

        for (int row = 0; row < height; row++) {
            for (int col = 0; col < width; col++) {
                if (matrix[row][col] == ‘1‘) {
                    dp[row + 1][col + 1] = Math.min(Math.min(dp[row + 1][col], dp[row][col + 1]), dp[row][col]) + 1;
                    maxSide = Math.max(maxSide, dp[row + 1][col + 1]);
                }
            }
        }
        return maxSide * maxSide;
    }
}