FastPrepFirst Non-Repeating Character
Problem · String

First Non-Repeating Character

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Problem statement

Given a non-empty string s, return the first character whose total frequency in the string is exactly one.

The problem statement continues
Pro

Examples

Example 1

s = "swiss"return = "w"

The first s repeats, while w occurs once.

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Reported in 1 Amazon interview this week

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CodePython 3
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FastPrep Pro
Reported in 1 Amazon interview this week

Unlock this recently reported problem

FastPrep Pro gives you full access to interview problems reported within the last week.

  • Full problem statement and constraints
  • 2 more worked examples, explained
  • Guided hints and editorial
  • Run your code on real test cases
$8.25/month

$99 billed yearly — or $19 month-to-month. Cancel anytime.

Free plan — 2 of 2 free unlocks used this week