Detect the Repeated Entry

Intermediate

A submission form should reject a batch if any value appears twice. Report whether a list contains any duplicate.

Implement `solve(List<Integer> nums)` to return true if the list contains any duplicate value, false otherwise.

Examples

Input[1, 2, 3, 2, 5]

Outputtrue

Input[1, 2, 3]

Outputfalse

Hints

If a Set built from the list is smaller than the list, there were duplicates.

Anonymous Apex

Boolean solve(List<Integer> nums) {
    // return true if any value repeats
    return null;
}

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