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+---
+id: complement-of-base-10-integer
+title: Complement of Base 10 Integer
+sidebar_label: 1009-Complement of Base 10 Integer
+tags:
+ - Bit Manipulation
+ - LeetCode
+ - Java
+ - Python
+ - C++
+description: "This is a solution to the Complement of Base 10 Integer problem on LeetCode."
+sidebar_position: 15
+---
+
+## Problem Description
+
+The complement of an integer is the integer you get when you flip all the 0's to 1's and all the 1's to 0's in its binary representation.
+
+For example, The integer 5 is "101" in binary and its complement is "010" which is the integer 2. Given an integer `n`, return its complement.
+
+### Examples
+
+**Example 1:**
+
+```
+Input: n = 5
+Output: 2
+Explanation: 5 is "101" in binary, with complement "010" in binary, which is 2 in base-10.
+```
+
+**Example 2:**
+
+```
+Input: n = 7
+Output: 0
+Explanation: 7 is "111" in binary, with complement "000" in binary, which is 0 in base-10.
+```
+
+**Example 3:**
+
+```
+Input: n = 10
+Output: 5
+Explanation: 10 is "1010" in binary, with complement "0101" in binary, which is 5 in base-10.
+```
+
+### Constraints
+
+- `0 <= n < 10^9`
+
+---
+
+## Solution for Complement of Integer Problem
+
+To solve this problem, we need to flip all bits of the binary representation of the given integer `n`.
+
+### Approach
+
+1. **Brute Force:**
+ - Convert the integer to its binary string representation.
+ - Flip each bit and convert the binary string back to an integer.
+
+2. **Optimized Approach:**
+ - Find the number of bits in the binary representation of `n`.
+ - Create a mask with the same number of bits set to 1.
+ - XOR `n` with the mask to get the complement.
+
+### Code in Different Languages
+
+