Update 221_Maximal_Square.java

Author: Sean Prashad

Dynamic Programming/221_Maximal_Square.java

@@ -4,19 +4,18 @@ public int maximalSquare(char[][] matrix) {
             return 0;
         }
 
-        int m = matrix.length, n = matrix[0].length;
-        int[][] dp = new int[m + 1][n + 1];
-        int result = 0;
+        int maxSquareLen = 0;
+        int[][] dp = new int[matrix.length + 1][matrix[0].length + 1];
 
-        for (int i = 1; i <= m; i++) {
-            for (int j = 1; j <= n; j++) {
+        for (int i = 1; i <= matrix.length; i++) {
+            for (int j = 1; j <= matrix[0].length; j++) {
                 if (matrix[i - 1][j - 1] == '1') {
-                    dp[i][j] = Math.min(dp[i - 1][j - 1], Math.min(dp[i - 1][j], dp[i][j - 1])) + 1;
-                    result = Math.max(result, dp[i][j]);
+                    dp[i][j] = 1 + Math.min(Math.min(dp[i][j - 1], dp[i - 1][j]), dp[i - 1][j - 1]);
+                    maxSquareLen = Math.max(maxSquareLen, dp[i][j]);
                 }
             }
         }
 
-        return result * result;
+        return maxSquareLen * maxSquareLen;
     }
 }