Score : $200$ points

问题描述

在由 $N$ 个正整数组成的序列 $a = (a_1, a_2, \dots, a_N)$ 中，有多少个不同的整数？

以上为通义千问 qwen-max 翻译，仅供参考。

Problem Statement

In a sequence of $N$ positive integers $a = (a_1, a_2, \dots, a_N)$, how many different integers are there?

Constraints

• $1 \leq N \leq 1000$
• $1 \leq a_i \leq 10^9 \, (1 \leq i \leq N)$
• All values in input are integers.

Input

Input is given from Standard Input in the following format:

$N$

$a_1$ $\ldots$ $a_N$

Output

Print the answer.

Sample Input 1

6
1 4 1 2 2 1

Sample Output 1

3

There are three different integers: $1, 2, 4$.

Sample Input 2

1
1

Sample Output 2

1

Sample Input 3

11
3 1 4 1 5 9 2 6 5 3 5

Sample Output 3

7

update @ 2024/3/10 10:20:29