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First Non-Repeating Character | Dataford Interview Questions - Dataford - Ace your Interview

All questions/Coding/First Non-Repeating Character

First Non-Repeating Character

Easy

Coding

Asked at 1 company1ArraysStringsHash Tables

Also asked at

Problem

Given a string s, return the first character that appears exactly once in left-to-right order. If no such character exists, return "".

Examples

Example 1

Inputs = "leetcode"Output"l"WhyThe first character with frequency 1 is `l`.

Example 2

Inputs = "aabb"Output""WhyNo character appears exactly once.

Constraints

`0 <= len(s) <= 10^5`
`s` contains printable characters
Return the first unique character in original order

Problem

Given a string s, return the first character that appears exactly once in left-to-right order. If no such character exists, return "".

Examples

Example 1

Inputs = "leetcode"Output"l"WhyThe first character with frequency 1 is `l`.

Example 2

Inputs = "aabb"Output""WhyNo character appears exactly once.

Constraints

`0 <= len(s) <= 10^5`
`s` contains printable characters
Return the first unique character in original order

Practice Python

Python 3.10

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

All questions/Coding/First Non-Repeating Character

First Non-Repeating Character

Easy

Coding

Asked at 1 company1ArraysStringsHash Tables

Also asked at

Problem

Given a string s, return the first character that appears exactly once in left-to-right order. If no such character exists, return "".

Examples

Example 1

Inputs = "leetcode"Output"l"WhyThe first character with frequency 1 is `l`.

Example 2

Inputs = "aabb"Output""WhyNo character appears exactly once.

Constraints

`0 <= len(s) <= 10^5`
`s` contains printable characters
Return the first unique character in original order

Problem

Given a string s, return the first character that appears exactly once in left-to-right order. If no such character exists, return "".

Examples

Example 1

Inputs = "leetcode"Output"l"WhyThe first character with frequency 1 is `l`.

Example 2

Inputs = "aabb"Output""WhyNo character appears exactly once.

Constraints

`0 <= len(s) <= 10^5`
`s` contains printable characters
Return the first unique character in original order

Practice Python

Python 3.10

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