欢迎来到起遇信息学
起遇信息学正处于上线筹建阶段,以下功能已全部开放免费体验: ✅ 完整题库浏览与代码提交评测(C / C++ / Python / Java 等) ✅ 入门到进阶的系列课程试读、作业与考试 ✅ AI 提示、AI 作业分析等智能助教功能 ✅ 赛事模拟与个人能力报告 ✅ 邮箱注册开放 ⏳ 付费课程订阅与微信/支付宝支付通道 ⏳ 手机号登录,微信扫码登录、微信公众号绑定 使用中如遇任何问题,欢迎通过页面底部 **"联系我们"** 与我们沟通。
CF1762A.Divide and Conquer
Divide and Conquer
An array is good if the sum of elements of is even.
You are given an array consisting of positive integers. In one operation, you can select an index and change .
Find the minimum number of operations (possibly ) needed to make good. It can be proven that it is always possible to make good.
denotes the floor function — the largest integer less than or equal to . For example, , and .
Input
Each test contains multiple test cases. The first line contains a single integer () — the number of test cases. The description of the test cases follows.
The first line of each test case contains a single integer () — the length of the array .
The second line of each test case contains space-separated integers () — representing the array .
Do note that the sum of over all test cases is not bounded.
Output
For each test case, output the minimum number of operations needed to make good.
Note
In the first test case, array is already good.
In the second test case, we can perform on index twice. After the first operation, array becomes . After performing on index again, becomes , which is good. It can be proved that it is not possible to make good in less number of operations.
In the third test case, becomes if we perform the operation on index once. As is good, answer is .
In the fourth test case, we need to perform the operation on index four times. After all operations, becomes . It can be proved that it is not possible to make good in less number of operations.
Samples
4
4
1 1 1 1
2
7 4
3
1 2 4
1
15
0
2
1
4
在线编程 IDE
建议全屏模式获得最佳体验
| 进入全屏编程 | Alt+E |
| 递交评测 | Ctrl+Enter |
| 注释/取消注释 | Ctrl+/ |
| 缩放字体 | Ctrl+滚轮 |