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Find Doubles

🤘 INTERN📚RELATED PROBLEMS

Given a list of N integers, not necessarily unique, find all elements of the list for which there exists exactly one element of the list which is twice that number. The integers range from 0 to 1000. The list has no more than 100,000 elements.

Your code should find the appropriate values and print them to STDOUT in sorted order.

Example 1:

Input:  numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 8]
Output: [0, 1, 2, 3] 
Explanation:
      
        8 is 4*2, but 8 is present twice, 0 is its own double, so it's part of the result.

Example 2:

Input:  numbers = [7, 17, 11, 1, 23]
Output: [] 
Explanation:
      
        Nothing is exactly twice another element.

Example 3:

Input:  numbers = [1, 1, 2]
Output: [1, 1] 
Explanation:
      
        1 and 1 both have their double 2 present, and 2 is present in the list only once.

Constraints:

TO-DO