Solution: Complement of Base 10 Integer

Statement

For any $n$ positive number in base 10, return the complement of its binary representation as an integer in base 10.

Constraints

• $0 \leq n \leq 10^9$

Solution

So far, you’ve probably brainstormed some approaches and have an idea of how to solve this problem. Let’s explore some of these approaches and figure out which one to follow based on considerations such as time complexity and any implementation constraints.

Naive approach

To calculate the complement of any integer, we need to perform the following steps:

1. Convert the integer to its binary value.

2. Once we have the binary value, we can use a loop to incrementally convert each $1$ to $0$ and each $0$ to $1$.

3. Now that we have the complemented binary number, we can convert it to its ...