chore: add LeetCode daily solution

Author: TechnoBlogger14o3

Easy/2026-03-05-1758-Minimum-Changes-To-Make-Alternating-Binary-String/explanation.md

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+# Minimum Changes To Make Alternating Binary String (Easy)
+
+**Problem ID:** 1758  
+**Date:** 2026-03-05  
+**Link:** https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string/
+
+## Approach
+
+To solve the problem of converting a binary string into an alternating format with the minimum number of changes, we can follow a systematic approach:
+
+### Approach:
+
+1. **Understanding Alternating Patterns**:
+   An alternating binary string can start with either '0' or '1'. Therefore, there are two possible valid patterns for a string of length `n`:
+   - Pattern A: "010101..." (starts with '0')
+   - Pattern B: "101010..." (starts with '1')
+
+2. **Count Mismatches**:
+   We will iterate through the given string `s` and compare each character to the expected character in both patterns (A and B). For each index `i`:
+   - If `s[i]` does not match the expected character in Pattern A, we increment a mismatch counter for Pattern A.
+   - Similarly, if `s[i]` does not match the expected character in Pattern B, we increment a mismatch counter for Pattern B.
+
+3. **Calculate Minimum Changes**:
+   After completing the iteration, we will have two counts:
+   - `changesA`: Number of changes needed to convert `s` to Pattern A.
+   - `changesB`: Number of changes needed to convert `s` to Pattern B.
+   The result will be the minimum of these two counts, i.e., `min(changesA, changesB)`.
+
+### Data Structures:
+- We primarily use integer counters to keep track of mismatches for both patterns, which requires O(1) space. The iteration through the string requires O(n) time.
+
+### Complexity:
+- **Time Complexity**: O(n), where `n` is the length of the string `s`. We traverse the string once to count mismatches.
+- **Space Complexity**: O(1), as we only use a fixed number of extra variables for counting.
+
+This approach efficiently determines the minimum number of changes required to transform the input string into an alternating binary string by leveraging direct comparison to the expected patterns.

Easy/2026-03-05-1758-Minimum-Changes-To-Make-Alternating-Binary-String/solution.java

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+class Solution {
+    public int minOperations(String s) {
+        int count1 = 0, count2 = 0;
+        for (int i = 0; i < s.length(); i++) {
+            char expectedChar = (i % 2 == 0) ? '0' : '1';
+            if (s.charAt(i) != expectedChar) {
+                count1++;
+            }
+            expectedChar = (i % 2 == 0) ? '1' : '0';
+            if (s.charAt(i) != expectedChar) {
+                count2++;
+            }
+        }
+        return Math.min(count1, count2);
+    }
+}

Easy/2026-03-05-1758-Minimum-Changes-To-Make-Alternating-Binary-String/solution.js

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+var minOperations = function(s) {
+    let count1 = 0, count2 = 0;
+    
+    for (let i = 0; i < s.length; i++) {
+        const expectedChar1 = i % 2 === 0 ? '0' : '1';
+        const expectedChar2 = i % 2 === 0 ? '1' : '0';
+        
+        if (s[i] !== expectedChar1) count1++;
+        if (s[i] !== expectedChar2) count2++;
+    }
+    
+    return Math.min(count1, count2);
+};

Easy/2026-03-05-1758-Minimum-Changes-To-Make-Alternating-Binary-String/solution.py

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+class Solution:
+    def minOperations(self, s: str) -> int:
+        count1 = count2 = 0
+        for i in range(len(s)):
+            expected_char1 = '0' if i % 2 == 0 else '1'
+            expected_char2 = '1' if i % 2 == 0 else '0'
+            if s[i] != expected_char1:
+                count1 += 1
+            if s[i] != expected_char2:
+                count2 += 1
+        return min(count1, count2)

README.md

@@ -383,3 +383,4 @@ Through completing the Blind 75 and NeetCode 150, you will have mastered:
 - 2026-03-02 — [Minimum Swaps to Arrange a Binary Grid](https://leetcode.com/problems/minimum-swaps-to-arrange-a-binary-grid/) (Medium) → `Medium/2026-03-02-1536-Minimum-Swaps-to-Arrange-a-Binary-Grid`
 - 2026-03-03 — [Find Kth Bit in Nth Binary String](https://leetcode.com/problems/find-kth-bit-in-nth-binary-string/) (Medium) → `Medium/2026-03-03-1545-Find-Kth-Bit-in-Nth-Binary-String`
 - 2026-03-04 — [Special Positions in a Binary Matrix](https://leetcode.com/problems/special-positions-in-a-binary-matrix/) (Easy) → `Easy/2026-03-04-1582-Special-Positions-in-a-Binary-Matrix`
+- 2026-03-05 — [Minimum Changes To Make Alternating Binary String](https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string/) (Easy) → `Easy/2026-03-05-1758-Minimum-Changes-To-Make-Alternating-Binary-String`