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First Unique Character Index

Easy

ArraysStrings

Problem

Given a string s, return the index of the first character that appears exactly once. If no such character exists, return -1. The input is a single string, and the output is a single integer index.

Constraints

1 <= len(s) <= 10^5
s consists of lowercase English letters

Problem

Constraints

1 <= len(s) <= 10^5
s consists of lowercase English letters

Practice Python

Python 3.10

Open on desktop for the full Python editor with syntax highlighting and autocomplete.

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First Unique Character Index

Easy

ArraysStrings

Problem

Constraints

1 <= len(s) <= 10^5
s consists of lowercase English letters

Problem

Constraints

1 <= len(s) <= 10^5
s consists of lowercase English letters

Practice Python

Python 3.10

Open on desktop for the full Python editor with syntax highlighting and autocomplete.

Up next

First Unique Character IndexEasy

First Non-Repeating CharacterEasy First Unique Character IndexEasy

Next question

First Unique Character Index | Dataford Interview Questions