A13073 | New Year and Ascent Sequence
时间限制1s
内存限制256MB
通过 / 提交0/0
题目描述
A sequence $a = [a_1, a_2, \ldots, a_l]$ of length $l$ has an ascent if there exists a pair of indices $(i, j)$ such that $1 \le i < j \le l$ and $a_i < a_j$ . For example, the sequence $[0, 2, 0, 2, 0]$ has an ascent because of the pair $(1, 4)$ , but the sequence $[4, 3, 3, 3, 1]$ doesn't have an ascent.
Let's call a concatenation of sequences $p$ and $q$ the sequence that is obtained by writing down sequences $p$ and $q$ one right after another without changing the order. For example, the concatenation of the $[0, 2, 0, 2, 0]$ and $[4, 3, 3, 3, 1]$ is the sequence $[0, 2, 0, 2, 0, 4, 3, 3, 3, 1]$ . The concatenation of sequences $p$ and $q$ is denoted as $p+q$ .
Gyeonggeun thinks that sequences with ascents bring luck. Therefore, he wants to make many such sequences for the new year. Gyeonggeun has $n$ sequences $s_1, s_2, \ldots, s_n$ which may have different lengths.
Gyeonggeun will consider all $n^2$ pairs of sequences $s_x$ and $s_y$ ( $1 \le x, y \le n$ ), and will check if its concatenation $s_x + s_y$ has an ascent. Note that he may select the same sequence twice, and the order of selection matters.
Please count the number of pairs ( $x, y$ ) of sequences $s_1, s_2, \ldots, s_n$ whose concatenation $s_x + s_y$ contains an ascent.
Let's call a concatenation of sequences $p$ and $q$ the sequence that is obtained by writing down sequences $p$ and $q$ one right after another without changing the order. For example, the concatenation of the $[0, 2, 0, 2, 0]$ and $[4, 3, 3, 3, 1]$ is the sequence $[0, 2, 0, 2, 0, 4, 3, 3, 3, 1]$ . The concatenation of sequences $p$ and $q$ is denoted as $p+q$ .
Gyeonggeun thinks that sequences with ascents bring luck. Therefore, he wants to make many such sequences for the new year. Gyeonggeun has $n$ sequences $s_1, s_2, \ldots, s_n$ which may have different lengths.
Gyeonggeun will consider all $n^2$ pairs of sequences $s_x$ and $s_y$ ( $1 \le x, y \le n$ ), and will check if its concatenation $s_x + s_y$ has an ascent. Note that he may select the same sequence twice, and the order of selection matters.
Please count the number of pairs ( $x, y$ ) of sequences $s_1, s_2, \ldots, s_n$ whose concatenation $s_x + s_y$ contains an ascent.
输入格式
The first line contains the number $n$ ( $1 \le n \le 100\,000$ ) denoting the number of sequences.
The next $n$ lines contain the number $l_i$ ( $1 \le l_i$ ) denoting the length of $s_i$ , followed by $l_i$ integers $s_{i, 1}, s_{i, 2}, \ldots, s_{i, l_i}$ ( $0 \le s_{i, j} \le 10^6$ ) denoting the sequence $s_i$ .
It is guaranteed that the sum of all $l_i$ does not exceed $100\,000$ .
The next $n$ lines contain the number $l_i$ ( $1 \le l_i$ ) denoting the length of $s_i$ , followed by $l_i$ integers $s_{i, 1}, s_{i, 2}, \ldots, s_{i, l_i}$ ( $0 \le s_{i, j} \le 10^6$ ) denoting the sequence $s_i$ .
It is guaranteed that the sum of all $l_i$ does not exceed $100\,000$ .
输出格式
Print a single integer, the number of pairs of sequences whose concatenation has an ascent.
输入输出样例
输入 #1
5 1 1 1 1 1 2 1 4 1 3
输出 #1
9
输入 #2
3 4 2 0 2 0 6 9 9 8 8 7 7 1 6
输出 #2
7
输入 #3
10 3 62 24 39 1 17 1 99 1 60 1 64 1 30 2 79 29 2 20 73 2 85 37 1 100
输出 #3
72
For the first example, the following $9$ arrays have an ascent: $[1, 2], [1, 2], [1, 3], [1, 3], [1, 4], [1, 4], [2, 3], [2, 4], [3, 4]$ . Arrays with the same contents are counted as their occurences.
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