solves minimum changes to make a binary string

Author: anishLearnsToCode

README.md

@@ -429,7 +429,7 @@
 | 1742 | [Maximum Number of Balls in a Box](https://leetcode.com/problems/maximum-number-of-balls-in-a-box)                                                        |                                                           [![Java](assets/java.png)](src/MaximumNumberOfBallsInABox.java)                                                            |                                                                                                                                   |
 | 1748 | [Sum of Unique Elements](https://leetcode.com/problems/sum-of-unique-elements)                                                                            |                                                               [![Java](assets/java.png)](src/SumOfUniqueElements.java)                                                               |                                                                                                                                   |
 | 1752 | [Check if Array Is Sorted and Rotated](https://leetcode.com/problems/check-if-array-is-sorted-and-rotated)                                                |                                                         [![Java](assets/java.png)](src/CheckIfArrayIsSortedAndRotated.java)                                                          |                                                                                                                                   |
-| 1758 | [Minimum Changes To Make Alternating Binary String](https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string)                      |                                                                                                                                                                                      |                                                                                                                                   |
+| 1758 | [Minimum Changes To Make Alternating Binary String](https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string)                      |                                                   [![Java](assets/java.png)](src/MinimumChangesToMakeAlternatingBinaryString.java)                                                   |                                                                                                                                   |
 | 1763 | [Longest Nice Substring](https://leetcode.com/problems/longest-nice-substring)                                                                            |                                                                                                                                                                                      |                                                                                                                                   |
 | 1768 | [Merge Strings Alternately](https://leetcode.com/problems/merge-strings-alternately)                                                                      |                                                                                                                                                                                      |                                                                                                                                   |
 | 1773 | [Count Items Matching a Rule](https://leetcode.com/problems/count-items-matching-a-rule)                                                                  |                                                                                                                                                                                      |                                                                                                                                   |

src/MinimumChangesToMakeAlternatingBinaryString.java

@@ -0,0 +1,16 @@
+public class MinimumChangesToMakeAlternatingBinaryString {
+    public int minOperations(String s) {
+        return Math.min(
+                    operationsToChangeIntoAlternatingString(s, '1'),
+                    operationsToChangeIntoAlternatingString(s, '0')
+                );
+    }
+
+    private int operationsToChangeIntoAlternatingString(String s, char start) {
+        int changes = 0, current = start - '0';
+        for (int index = 0 ; index < s.length() ; index++, current ^= 1) {
+            if (s.charAt(index) != current + '0') changes++;
+        }
+        return changes;
+    }
+}