Desafío de programación Remove Duplicates

Problema

Return the list with repeated values removed, keeping the first occurrence of each value in its original order.

Implement remove_duplicates(numbers).

numbers: The list of integers.

Return the list without duplicates.

0 ≤ length ≤ 100,000

Ejemplo 1

Entrada:
numbers = [3, 1, 3, 2, 1]

Salida esperada:
expected = [3, 1, 2]

Entrada:
std::vector<long long> numbers = {3, 1, 3, 2, 1};

Salida esperada:
std::vector<long long> expected = {3, 1, 2};

Entrada:
long[] numbers = new long[] {3, 1, 3, 2, 1};

Salida esperada:
long[] expected = new long[] {3, 1, 2};

Keep 3, 1, then 2; the later 3 and 1 are dropped: [3, 1, 2].

Ejemplo 2

Entrada:
numbers = [7, 7, 7]

Salida esperada:
expected = [7]

Entrada:
std::vector<long long> numbers = {7, 7, 7};

Salida esperada:
std::vector<long long> expected = {7};

Entrada:
long[] numbers = new long[] {7, 7, 7};

Salida esperada:
long[] expected = new long[] {7};

Only the first 7 stays: [7].

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