First Non-Repeating Problem

First Non-Repeating Problem — ExecCode Easy DSA Practice

Solve the First Non-Repeating problem on ExecCode. Free online easy DSA practice in Strings - Basics. Write and run code in Java, C++, Python — no signup required to run.

Problem description

Description You are given the input needed to solve First Non-Repeating. Your task is to compute the required answer and return first non-repeating char or -1. A text tool receives characters in a specific order. In First Non-Repeating, the answer depends on handling those characters carefully, including duplicates and order. s: input string.

Examples

Input {"s": "swiss"}; Output w. Input {"s": "racecar"}; Output e. Input {"s": "aabb"}; Output -1

Constraints

1 <= len(s) <= 10^5

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