You are given a string s and a robot equipped with an empty string t and an empty output string p.

The robot can perform either of the following two operations in any order until both s and t become empty:

1. Remove the first character from s and append it to the end of t.

2. Remove the last character from t and append it to the end of p.

Return the lexicographically smallest string p that can be produced.

Constraints:

• $1 \leq$ s.length $\leq 10^5$

• s consists of only English lowercase letters.

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.