Find Duplicate Transaction IDs | Dataford Interview Questions

Write a function to identify duplicates in a list of transaction IDs.

Return each duplicated ID exactly once, in the order its repetition is first detected. Return an empty list when no ID appears more than once.

Input: a list of strings. Output: a list of strings.

Example: ['tx1', 'tx2', 'tx1', 'tx3', 'tx2'] returns ['tx1', 'tx2'].

Constraints: The list contains 0 to 100,000 IDs, each ID is a non-empty string.

def identify_duplicates(transaction_ids):

Your question is Find Duplicate Transaction IDs. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Write a function to identify duplicates in a list of transaction IDs.

Return each duplicated ID exactly once, in the order its repetition is first detected. Return an empty list when no ID appears more than once.

Input: a list of strings. Output: a list of strings.

Example: ['tx1', 'tx2', 'tx1', 'tx3', 'tx2'] returns ['tx1', 'tx2'].

Constraints: The list contains 0 to 100,000 IDs, each ID is a non-empty string.

def identify_duplicates(transaction_ids):

Your question is Find Duplicate Transaction IDs. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.