Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area.
For example, given the following matrix:
使用动态规划的方式可以非常好的进行处理
java
public class Solution { /** * @param matrix: a matrix of 0 and 1 * @return: an integer */ public int maxSquare(int[][] arr) { // write your code here if (arr == null || arr.length == 0 || arr[0] == null || arr[0].length == 0) { return 0; } int[][] f = new int[arr.length][arr[0].length]; int max = Integer.MIN_VALUE; for (int i = 0; i < arr.length; i++) { f[i][0] = arr[i][0]; max = Math.max(max, arr[i][0]); } for (int i = 0; i < arr[0].length; i++) { f[0][i] = arr[0][i]; max = Math.max(max, arr[0][i]); } for (int i = 1; i < arr.length; i++) { for (int j = 1; j < arr[i].length; j++) { if (arr[i][j] == 1) { f[i][j] = Math.min(f[i - 1][j], Math.min(f[i][j - 1], f[i - 1][j - 1])) + 1; } else { f[i][j] = 0; } max = Math.max(max, f[i][j]); } } return max * max; } }