solves search in 2d matrix ii in java

Author: anishLearnsToCode

Diff for: README.md

@@ -193,7 +193,7 @@
 | 236  | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree)                                          |                                                        [![Java](assets/java.png)](src/LowestCommonAncestorOfBinaryTree.java)                                                         |                                                                                                                                   |
 | 237  | [Delete a Node In A Linked List](https://leetcode.com/problems/delete-node-in-a-linked-list)                                                              |                          [![Java](assets/java.png)](src/DeleteANodeInLinkedList.java) [![Python](assets/python.png)](python/delete_node_in_linked_list.py)                           |                                                                                                                                   |
 | 238  | [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self)                                                                |                                                           [![Java](assets/java.png)](src/ProductOfArrayExceptItself.java)                                                            |                                                                                                                                   |
-| 240  | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii)                                                                              |                                                                                                                                                                                      |                                                                                                                                   |
+| 240  | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii)                                                                              |                                                                [![Java](assets/java.png)](src/SearchA2DMatrixII.java)                                                                |                                                                                                                                   |
 | 241  | [Different Ways to Add Parentheses](https://leetcode.com/problems/different-ways-to-add-parentheses)                                                      |                                                                                                                                                                                      |                                                                                                                                   |
 | 242  | [Valid Anagram](https://leetcode.com/problems/valid-anagram)                                                                                              |                                [![Java](assets/java.png)](src/ValidAnagram.java) [![Python](assets/python.png)](python/delete_node_in_linked_list.py)                                |                                                                                                                                   |
 | 243  | 🔒 [Shortest Word Distance](https://leetcode.com/problems/shortest-word-distance)                                                                         |                                                                                                                                                                                      |                                                                                                                                   |

Diff for: src/SearchA2DMatrixII.java

@@ -0,0 +1,15 @@
+// https://leetcode.com/problems/search-a-2d-matrix-ii
+// T: O(m + n)
+// S: O(1)
+
+public class SearchA2DMatrixII {
+    public boolean searchMatrix(int[][] matrix, int target) {
+        final int rows = matrix.length, columns = matrix[0].length;
+        for (int column = columns - 1, row = 0 ; row < rows && column >= 0 ; ) {
+            if (matrix[row][column] == target) return true;
+            else if (matrix[row][column] < target) row++;
+            else column--;
+        }
+        return false;
+    }
+}