You are given a string, str, as a binary representation of an integer. Your task is to return the number of steps needed to reduce it to $1$ by following these rules:

• If the number is even, divide it by $2$.

• If the number is odd, add $1$ to it.

You can always reach 1 for all provided test cases.

Constraints:

• $1 <=$str.length $<= 500$

• str consists of characters $'0'$ or $'1'$.

• $str[0] ==$ $'1'$

Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding on how to solve this problem.

Implement your solution in the following coding playground.