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/ Remove Duplicates

Case Sensitive

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Remove Duplicates

Remove duplicate lines from text while preserving the first occurrence

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What is duplicate removal?

Duplicate removal is the process of identifying and eliminating repeated entries from a list or text. This tool helps clean up data by keeping only unique entries while maintaining the original order and preserving the…

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How does it work?

Removal Process This tool removes duplicate lines from your text, keeping only the first occurrence of each unique line. The order of lines is preserved. Case Sensitivity When case-sensitive mode is off (default), 'Appl…

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Sample Cases

Covers Basic duplicate removal, Case insensitive (default), and Case sensitive so you can compare common inputs and outputs quickly.

/ Code

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/ Integration

Source code from the selected tool, shown here alongside the live version on the right.

/ Source Code

TypeScript

typescript

type RemoveDuplicatesOptions = {
  caseSensitive: boolean;
};

function removeDuplicates(input: string, options: RemoveDuplicatesOptions): string {
  const lines = input.split('\n');
  const seen = new Set<string>();
  const uniqueLines: string[] = [];

  lines.forEach((line) => {