solves delete columns to make sorted

Author: anishLearnsToCode

README.md

@@ -256,7 +256,7 @@
 | 938 | [Range Sum of BST](https://leetcode.com/problems/range-sum-of-bst) | [![Java](assets/java.png)](src/RangeSumOfBST.java) |
 | 941 | [Valid Mountain Array](https://leetcode.com/problems/valid-mountain-array) | [![Java](assets/java.png)](src/ValidMountainArray.java) [![Python](assets/python.png)](python/valid_mountain_array.py) |
 | 942 | [DI String Match](https://leetcode.com/problems/di-string-match) | [![Java](assets/java.png)](src/DIStringMatch.java) |
-| 944 | [Delete Columns to Make Sorted](https://leetcode.com/problems/delete-columns-to-make-sorted) | |
+| 944 | [Delete Columns to Make Sorted](https://leetcode.com/problems/delete-columns-to-make-sorted) | [![Java](assets/java.png)](src/DeleteColumnsToMakeSorted.java) |
 | 949 | [Largest Time for Given Digits](https://leetcode.com/problems/largest-time-for-given-digits) | |
 | 953 | [Verifying an Alien Dictionary](https://leetcode.com/problems/verifying-an-alien-dictionary) | |
 | 961 | [N-Repeated Elements in Size 2N Array](https://leetcode.com/problems/n-repeated-element-in-size-2n-array) | |

src/DeleteColumnsToMakeSorted.java

@@ -0,0 +1,17 @@
+public class DeleteColumnsToMakeSorted {
+    public int minDeletionSize(String[] strings) {
+        final int columns = strings[0].length();
+        int deletions = 0;
+        for (int column = 0 ; column < columns ; column++) {
+            if (!isSorted(strings, column)) deletions++;
+        }
+        return deletions;
+    }
+
+    private boolean isSorted(String[] strings, int column) {
+        for (int row = 1 ; row < strings.length ; row++) {
+            if (strings[row].charAt(column) < strings[row - 1].charAt(column)) return false;
+        }
+        return true;
+    }
+}