Unique Values (Easy version) · Interview Problem

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Codeforces

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Unique Values (Easy version)

Count how many distinct values appear in each test case, using the easy-version constraints.

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Unique Values

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Problem Statement

Problem

You are given an array of integers. Your task is to determine how many distinct values appear in the array.

For each test case, output the number of different elements present in the array.

This is the easy version of the problem, so the constraints are intended to allow straightforward counting-based solutions.

Input Format

The first line contains an integer $t$ — the number of test cases.
For each test case:
- The first line contains an integer $n$ — the array length.
- The second line contains $n$ integers $a_1, a_2, \dots, a_n$ .

Output Format

For each test case, print a single integer — the number of distinct values in the array.

Constraints

$1 \le t$
$1 \le n$
The array elements fit in standard 32-bit signed integers.
Exact limits are omitted here; use a solution that is linear or near-linear per test case.

Examples

Sample cases returned by the problem API.

Example 1

Input

3
5
1 2 2 3 1
4
7 7 7 7
6
4 5 4 6 5 7

Output

3
1
4

Explanation

Test case 1: distinct values are {1, 2, 3}.
Test case 2: only {7} appears.
Test case 3: distinct values are {4, 5, 6, 7}.

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