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Solve a Basic Algorithm Problem
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Solve a Basic Algorithm Problem

EasyPython

Problem

Solve a common algorithm problem, such as reversing a string or finding duplicates in an array.

Implement find_duplicates(nums), which returns every value appearing at least twice in nums, listed once in the order it is first detected as a duplicate. Return an empty list when all values are unique. The input is a list of integers, and the output is a list of integers.

Constraints

  • 0 <= nums.length <= 500
  • -10^9 <= nums[i] <= 10^9
  • Return each duplicated value exactly once
  • Preserve the order in which duplicates are first detected

Function Signature

def find_duplicates(nums):
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