A15086 | All Distinct
时间限制1s
内存限制256MB
通过 / 提交0/0
题目描述
Sho has an array $a$ consisting of $n$ integers. An operation consists of choosing two distinct indices $i$ and $j$ and removing $a_i$ and $a_j$ from the array.
For example, for the array $[2, 3, 4, 2, 5]$ , Sho can choose to remove indices $1$ and $3$ . After this operation, the array becomes $[3, 2, 5]$ . Note that after any operation, the length of the array is reduced by two.
After he made some operations, Sho has an array that has only distinct elements. In addition, he made operations such that the resulting array is the longest possible.
More formally, the array after Sho has made his operations respects these criteria:
- No pairs such that ( $i < j$ ) and $a_i = a_j$ exist.
- The length of $a$ is maximized.
Output the length of the final array.
For example, for the array $[2, 3, 4, 2, 5]$ , Sho can choose to remove indices $1$ and $3$ . After this operation, the array becomes $[3, 2, 5]$ . Note that after any operation, the length of the array is reduced by two.
After he made some operations, Sho has an array that has only distinct elements. In addition, he made operations such that the resulting array is the longest possible.
More formally, the array after Sho has made his operations respects these criteria:
- No pairs such that ( $i < j$ ) and $a_i = a_j$ exist.
- The length of $a$ is maximized.
Output the length of the final array.
输入格式
The first line contains a single integer $t$ ( $1 \leq t \leq 10^3$ ) — the number of test cases.
The first line of each test case contains a single integer $n$ ( $1 \leq n \leq 50$ ) — the length of the array.
The second line of each test case contains $n$ integers $a_i$ ( $1 \leq a_i \leq 10^4$ ) — the elements of the array.
The first line of each test case contains a single integer $n$ ( $1 \leq n \leq 50$ ) — the length of the array.
The second line of each test case contains $n$ integers $a_i$ ( $1 \leq a_i \leq 10^4$ ) — the elements of the array.
输出格式
For each test case, output a single integer — the length of the final array. Remember that in the final array, all elements are different, and its length is maximum.
输入输出样例
输入 #1
4 6 2 2 2 3 3 3 5 9 1 9 9 1 4 15 16 16 15 4 10 100 1000 10000
输出 #1
2 1 2 4
For the first test case Sho can perform operations as follows:
1. Choose indices $1$ and $5$ to remove. The array becomes $[2, 2, 2, 3, 3, 3] \rightarrow [2, 2, 3, 3]$ .
2. Choose indices $1$ and $4$ to remove. The array becomes $[2, 2, 3, 3] \rightarrow [2, 3]$ .
The final array has a length of $2$ , so the answer is $2$ . It can be proven that Sho cannot obtain an array with a longer length.For the second test case Sho can perform operations as follows:
1. Choose indices $3$ and $4$ to remove. The array becomes $[9, 1, 9, 9, 1] \rightarrow [9, 1, 1]$ .
2. Choose indices $1$ and $3$ to remove. The array becomes $[9, 1, 1] \rightarrow [1]$ .
The final array has a length of $1$ , so the answer is $1$ . It can be proven that Sho cannot obtain an array with a longer length.
1. Choose indices $1$ and $5$ to remove. The array becomes $[2, 2, 2, 3, 3, 3] \rightarrow [2, 2, 3, 3]$ .
2. Choose indices $1$ and $4$ to remove. The array becomes $[2, 2, 3, 3] \rightarrow [2, 3]$ .
The final array has a length of $2$ , so the answer is $2$ . It can be proven that Sho cannot obtain an array with a longer length.For the second test case Sho can perform operations as follows:
1. Choose indices $3$ and $4$ to remove. The array becomes $[9, 1, 9, 9, 1] \rightarrow [9, 1, 1]$ .
2. Choose indices $1$ and $3$ to remove. The array becomes $[9, 1, 1] \rightarrow [1]$ .
The final array has a length of $1$ , so the answer is $1$ . It can be proven that Sho cannot obtain an array with a longer length.
C++ 编辑器
输入
输出
可保存默认模板；新题优先使用已保存模板。
当前快捷键仅展示，暂不支持修改。
- 撤销
Ctrl / ⌘ + Z - 重做
Ctrl / ⌘ + Y - 查找
Ctrl / ⌘ + F - 全选
Ctrl / ⌘ + A - 复制
Ctrl / ⌘ + C - 剪切
Ctrl / ⌘ + X - 粘贴
Ctrl / ⌘ + V - 自动排版
工具栏排版按钮 - 草稿保存
编辑时自动保存到本机
历史
提交记录
状态说明时间源码
AI
作答助手
你好，我是作答助手。可以问思路、复杂度、样例含义或代码报错原因；不会直接给出完整 AC 代码。
确定要清空代码吗？
提交通过
评测结果：Accepted