A story with a non-twin
An array of integers, of odd size (int *array[2N+1]), is such that each number in the array appears twice, apart from one (the non-twin).
Problem: find an algorithm accepting the array as input and returning the value of the non-twin
Problem 2: same question with a second non-twin in the array; the algorithm should return both of them.
Another insight problem: Petals around the Rose
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