Added task 3750

src/main/java/g3701_3800/s3750_minimum_number_of_flips_to_reverse_binary_string/Solution.java

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+package g3701_3800.s3750_minimum_number_of_flips_to_reverse_binary_string;
+
+// #Easy #String #Math #Two_Pointers #Bit_Manipulation #Mid_Level #Biweekly_Contest_170
+// #2026_04_26_Time_1_ms_(100.00%)_Space_42.88_MB_(49.74%)
+
+public class Solution {
+    public int minimumFlips(int n) {
+        int ans = 0;
+        int temp = n;
+        int l = 0;
+        int r = -1;
+        while (temp > 0) {
+            temp >>= 1;
+            r++;
+        }
+        while (l < r) {
+            ans += ((n >> l) & 1) ^ ((n >> r) & 1);
+            l++;
+            r--;
+        }
+        return 2 * ans;
+    }
+}

src/main/java/g3701_3800/s3750_minimum_number_of_flips_to_reverse_binary_string/readme.md

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+3750\. Minimum Number of Flips to Reverse Binary String
+
+Easy
+
+You are given a **positive** integer `n`.
+
+Let `s` be the **binary representation** of `n` without leading zeros.
+
+The **reverse** of a binary string `s` is obtained by writing the characters of `s` in the opposite order.
+
+You may flip any bit in `s` (change `0 → 1` or `1 → 0`). Each flip affects **exactly** one bit.
+
+Return the **minimum** number of flips required to make `s` equal to the reverse of its original form.
+
+**Example 1:**
+
+**Input:** n = 7
+
+**Output:** 0
+
+**Explanation:**
+
+The binary representation of 7 is `"111"`. Its reverse is also `"111"`, which is the same. Hence, no flips are needed.
+
+**Example 2:**
+
+**Input:** n = 10
+
+**Output:** 4
+
+**Explanation:**
+
+The binary representation of 10 is `"1010"`. Its reverse is `"0101"`. All four bits must be flipped to make them equal. Thus, the minimum number of flips required is 4.
+
+**Constraints:**
+
+*   <code>1 <= n <= 10<sup>9</sup></code>

src/test/java/g3701_3800/s3750_minimum_number_of_flips_to_reverse_binary_string/SolutionTest.java

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+package g3701_3800.s3750_minimum_number_of_flips_to_reverse_binary_string;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+class SolutionTest {
+    @Test
+    void minimumFlips() {
+        assertThat(new Solution().minimumFlips(7), equalTo(0));
+    }
+
+    @Test
+    void minimumFlips2() {
+        assertThat(new Solution().minimumFlips(10), equalTo(4));
+    }
+}