102782: [AtCoder]ABC278 C - FF
Description
Score : $300$ points
Problem Statement
Takahashi runs an SNS "Twidai," which has $N$ users from user $1$ through user $N$. In Twidai, users can follow or unfollow other users.
$Q$ operations have been performed since Twidai was launched. The $i$-th $(1\leq i\leq Q)$ operation is represented by three integers $T_i$, $A_i$, and $B_i$, whose meanings are as follows:
- If $T_i = 1$: it means that user $A_i$ follows user $B_i$. If user $A_i$ is already following user $B_i$ at the time of this operation, it does not make any change.
- If $T_i = 2$: it means that user $A_i$ unfollows user $B_i$. If user $A_i$ is not following user $B_i$ at the time of this operation, it does not make any change.
- If $T_i = 3$: it means that you are asked to determine if users $A_i$ and $B_i$ are following each other. You need to print
Yes
if user $A_i$ is following user $B_i$ and user $B_i$ is following user $A_i$, andNo
otherwise.
When the service was launched, no users were following any users.
Print the correct answers for all operations such that $T_i = 3$ in ascending order of $i$.
Constraints
- $2 \leq N \leq 10 ^ 9$
- $1 \leq Q \leq 2\times10 ^ 5$
- $T _ i=1,2,3\ (1\leq i\leq Q)$
- $1 \leq A _ i \leq N\ (1\leq i\leq Q)$
- $1 \leq B _ i \leq N\ (1\leq i\leq Q)$
- $A _ i\neq B _ i\ (1\leq i\leq Q)$
- There exists $i\ (1\leq i\leq Q)$ such that $T _ i=3$.
- All values in the input are integers.
Input
The input is given from Standard Input in the following format:
$N$ $Q$ $T _ 1$ $A _ 1$ $B _ 1$ $T _ 2$ $A _ 2$ $B _ 2$ $\vdots$ $T _ Q$ $A _ Q$ $B _ Q$
Output
Print $X$ lines, where $X$ is the number of $i$'s $(1\leq i\leq Q)$ such that $T _ i=3$. The $j$-th $(1\leq j\leq X)$ line should contain the answer to the $j$-th operation such that $T _ i=3$.
Sample Input 1
3 9 1 1 2 3 1 2 1 2 1 3 1 2 1 2 3 1 3 2 3 1 3 2 1 2 3 1 2
Sample Output 1
No Yes No No
Twidai has three users. The nine operations are as follows.
- User $1$ follows user $2$. No other users are following or followed by any users.
- Determine if users $1$ and $2$ are following each other. User $1$ is following user $2$, but user $2$ is not following user $1$, so
No
is the correct answer to this operation. - User $2$ follows user $1$.
- Determine if users $1$ and $2$ are following each other. User $1$ is following user $2$, and user $2$ is following user $1$, so
Yes
is the correct answer to this operation. - User $2$ follows user $3$.
- User $3$ follows user $2$.
- Determine if users $1$ and $3$ are following each other. User $1$ is not following user $3$, and user $3$ is not following user $1$, so
No
is the correct answer to this operation. - User $1$ unfollows user $2$.
- Determine if users $1$ and $2$ are following each other. User $2$ is following user $1$, but user $1$ is not following user $2$, so
No
is the correct answer to this operation.
Sample Input 2
2 8 1 1 2 1 2 1 3 1 2 1 1 2 1 1 2 1 1 2 2 1 2 3 1 2
Sample Output 2
Yes No
A user may follow the same user multiple times.
Sample Input 3
10 30 3 1 6 3 5 4 1 6 1 3 1 7 3 8 4 1 1 6 2 4 3 1 6 5 1 5 6 1 1 8 1 8 1 2 3 10 1 7 6 3 5 6 1 6 7 3 6 7 1 9 5 3 8 6 3 3 8 2 6 9 1 7 1 3 10 8 2 9 2 1 10 9 2 6 10 2 6 8 3 1 6 3 1 8 2 8 5 1 9 10
Sample Output 3
No No No No Yes Yes No No No Yes Yes
Input
题意翻译
【题目翻译】 洛谷是一个大平台,从前,这里有 $n$ 个用户。刚开始,他们没有任何关系。 有 $q$ 次操作,每组操作包含 $op_i$,$a_i$,$b_i$: + $op_i = 1$,表示 $a_i$ 关注了 $b_i$。 + $op_i = 2$,表示 $a_i$ 取关了 $b_i$。 + $op_i = 3$,表示查询 $a_i$ 与 $b_i$ 是否互关。 对于每个 $op_i = 3$,输出结果。 translated by @[liangbowen](https://www.luogu.com.cn/user/367488). 【输入格式】 第一行两个数 $n$,$q$。 接下来 $q$ 行,每行三个数 $op_i$,$a_i$,$b_i$。 【输出格式】 对于每个 $op_i = 3$,输出结果。 【数据范围】 $1 \le n \le 10^9$ $1 \le q \le 2 \times 10^5$ 保证 $1 \le a_i, b_i \le n$,且 $a_i \ne b_i$。 保证 $op_i \in \{1, 2, 3\}$。Output
问题描述
Takahashi 运营着一个名为“Twidai”的社交网络,拥有从用户1到用户N的N个用户。 在Twidai中,用户可以关注或取消关注其他用户。
自Twidai推出以来,已经执行了Q次操作。 第i次$(1≤i≤Q)$操作由三个整数$T_i$,$A_i$和$B_i$表示,其含义如下:
- 如果$T_i = 1$:表示用户$A_i$关注用户$B_i$。如果在执行此操作时用户$A_i$已经关注了用户$B_i$,则不会产生任何变化。
- 如果$T_i = 2$:表示用户$A_i$取消关注用户$B_i$。如果在执行此操作时用户$A_i$没有关注用户$B_i$,则不会产生任何变化。
- 如果$T_i = 3$:表示要求你判断用户$A_i$和$B_i$是否互相关注。如果用户$A_i$关注用户$B_i$且用户$B_i$关注用户$A_i$,则你需要打印
Yes
,否则打印No
。
服务推出时,没有用户关注任何用户。
按照$i$升序打印所有$T_i = 3$的操作的正确答案。
约束
- $2 ≤ N ≤ 10 ^ 9$
- $1 ≤ Q ≤ 2\times10 ^ 5$
- $T _ i=1,2,3\ (1≤i≤Q)$
- $1 ≤ A _ i ≤ N\ (1≤i≤Q)$
- $1 ≤ B _ i ≤ N\ (1≤i≤Q)$
- $A _ i\neq B _ i\ (1≤i≤Q)$
- 存在$i\ (1≤i≤Q)$使得$T _ i=3$。
- 输入中的所有值都是整数。
输入
输入将从标准输入以以下格式给出:
$N$ $Q$ $T _ 1$ $A _ 1$ $B _ 1$ $T _ 2$ $A _ 2$ $B _ 2$ $\vdots$ $T _ Q$ $A _ Q$ $B _ Q$
输出
打印X行,其中X是满足$T _ i=3$的i的数量。 第j行$(1≤j≤X)$应该包含满足$T _ i=3$的第j个操作的答案。
样例输入1
3 9 1 1 2 3 1 2 1 2 1 3 1 2 1 2 3 1 3 2 3 1 3 2 1 2 3 1 2
样例输出1
No Yes No No
Twidai有三个用户。 九次操作如下。
- 用户1关注用户2。没有其他用户关注或被任何用户关注。
- 判断用户1和2是否互相关注。用户1关注用户2,但用户2不关注用户1,因此此操作的正确答案是
No
。 - 用户2关注用户1。
- 判断用户1和2是否互相关注。用户1关注用户2,用户2关注用户1,因此此操作的正确答案是
Yes
。 - 用户2关注用户3。
- 用户3关注用户2。
- 判断用户1和3是否互相关注。用户1不关注用户3,用户3不关注用户1,因此此操作的正确答案是
No
。 - 用户1取消关注用户2。
- 判断用户1和2是否互相关注。用户2关注用户1,但用户1不关注用户2,因此此操作的正确答案是
No
。
样例输入2
2 8 1 1 2 1 2 1 3 1 2 1 1 2 1 1 2 1 1 2 2 1 2 3 1 2
样例输出2
Yes No
一个用户可以多次关注同一个用户。
样例输入3
10 30 3 1 6 3 5 4 1 6 1 3 1 7 3 8 4 1 1 6 2 4 3 1 6 5 1 5 6 1 1 8 1 8 1 2 3 10 1 7 6 3 5 6 1 6 7 3 6 7 1 9 5 3 8 6 3 3 8 2 6 9 1 7 1 3 10 8 2 9 2 1 10 9 2 6 10 2 6 8 3 1 6 3 1 8 2 8 5 1 9 10
样例输出3
No No No No Yes Yes No No No Yes Yes