A14572 | Artistic Partition
时间限制1s
内存限制256MB
通过 / 提交0/0
题目描述
For two positive integers $l$ and $r$ ( $l \le r$ ) let $c(l, r)$ denote the number of integer pairs $(i, j)$ such that $l \le i \le j \le r$ and $\operatorname{gcd}(i, j) \ge l$ . Here, $\operatorname{gcd}(i, j)$ is the [greatest common divisor (GCD)](https://en.wikipedia.org/wiki/Greatest_common_divisor) of integers $i$ and $j$ .
YouKn0wWho has two integers $n$ and $k$ where $1 \le k \le n$ . Let $f(n, k)$ denote the minimum of $\sum\limits_{i=1}^{k}{c(x_i+1,x_{i+1})}$ over all integer sequences $0=x_1 \lt x_2 \lt \ldots \lt x_{k} \lt x_{k+1}=n$ .
Help YouKn0wWho find $f(n, k)$ .
YouKn0wWho has two integers $n$ and $k$ where $1 \le k \le n$ . Let $f(n, k)$ denote the minimum of $\sum\limits_{i=1}^{k}{c(x_i+1,x_{i+1})}$ over all integer sequences $0=x_1 \lt x_2 \lt \ldots \lt x_{k} \lt x_{k+1}=n$ .
Help YouKn0wWho find $f(n, k)$ .
输入格式
The first line contains a single integer $t$ ( $1 \le t \le 3 \cdot 10^5$ ) — the number of test cases.
The first and only line of each test case contains two integers $n$ and $k$ ( $1 \le k \le n \le 10^5$ ).
The first and only line of each test case contains two integers $n$ and $k$ ( $1 \le k \le n \le 10^5$ ).
输出格式
For each test case, print a single integer — $f(n, k)$ .
输入输出样例
输入 #1
4 6 2 4 4 3 1 10 3
输出 #1
8 4 6 11
In the first test case, YouKn0wWho can select the sequence $[0, 2, 6]$ . So $f(6, 2) = c(1, 2) + c(3, 6) = 3 + 5 = 8$ which is the minimum possible.
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