You are given a binary string of length n where all characters are initially 0, indexed from 1 to n.

At each step i from 1 to n, the character at the 1-based index flips[i - 1] is flipped to 1.

A binary string is considered prefix aligned at step i if every character from index 1 to i is 1 and all other characters from index i + 1 to n are 0.

Return the total number of steps at which the binary string is prefix aligned.

Constraints:

• n is equal to flips.length

• $1 \leq$ n $\leq 5 \times 10^{4}$

• flips is a permutation of the integers in the range $[1,$ n$]$

Now, 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 of how to solve this problem.

Implement your solution in the following coding playground.