Codeforces Round 772 (Div. 2)
E
Cars
Codeforces
2200
原题
← DF →
翻译中…

There are $n$ cars on a coordinate axis $OX$. Each car is located at an integer point initially and no two cars are located at the same point. Also, each car is oriented either left or right, and they can move at any constant positive speed in that direction at any moment.

翻译中…

More formally, we can describe the $i$-th car with a letter and an integer: its orientation $ori_i$ and its location $x_i$. If $ori_i = L$, then $x_i$ is decreasing at a constant rate with respect to time. Similarly, if $ori_i = R$, then $x_i$ is increasing at a constant rate with respect to time.

翻译中…

We call two cars irrelevant if they never end up in the same point regardless of their speed. In other words, they won't share the same coordinate at any moment.

翻译中…

We call two cars destined if they always end up in the same point regardless of their speed. In other words, they must share the same coordinate at some moment.

翻译中…

Unfortunately, we lost all information about our cars, but we do remember $m$ relationships. There are two types of relationships:

翻译中…

$1$ $i$ $j$ —$i$-th car and $j$-th car are irrelevant.

翻译中…

$2$ $i$ $j$ —$i$-th car and $j$-th car are destined.

翻译中…

Restore the orientations and the locations of the cars satisfying the relationships, or report that it is impossible. If there are multiple solutions, you can output any.

翻译中…

Note that if two cars share the same coordinate, they will intersect, but at the same moment they will continue their movement in their directions.

翻译中…

Input

翻译中…

The first line contains two integers, $n$ and $m$ $(2 \leq n \leq 2 \cdot 10^5; 1 \leq m \leq min(2 \cdot 10^5, \frac{n(n-1)}{2})$ — the number of cars and the number of restrictions respectively.

翻译中…

Each of the next $m$ lines contains three integers, $type$, $i$, and $j$ $(1 \leq type \leq 2; 1 \leq i,j \leq n; i≠j)$.

翻译中…

If $type$ = $1$, $i$-th car and $j$-th car are irrelevant. Otherwise, $i$-th car and $j$-th car are destined.

翻译中…

It is guaranteed that for each pair of cars, there are at most $1$ relationship between.

翻译中…

Output

翻译中…

In the first line, print either "YES" or "NO" (in any case), whether it is possible to restore the orientations and the locations of the cars satisfying the relationships.

翻译中…

If the answer is "YES", print $n$ lines each containing a symbol and an integer: $ori_i$ and $x_i$ $(ori_i \in \{L, R\}; -10^9 \leq x_i \leq 10^9)$ — representing the information of the $i$-th car.

翻译中…

If the orientation is left, then $ori_i$ = $L$. Otherwise $ori_i$ = $R$.

翻译中…

$x_i$ is the where the $i$-th car is located. Note that all $x_i$ should be distinct.

翻译中…

We can prove that if there exists a solution, then there must be a solution satisfying the constraints on $x_i$.

翻译中…

样例

Input #1
4 4
1 1 2
1 2 3
2 3 4
2 4 1
Output #1
YES
R 0
L -3
R 5
L 6
InputCopy OutputCopy
Input #2
3 3
1 1 2
1 2 3
1 1 3
Output #2
NO
InputCopy OutputCopy
题目信息
题号
1635E
时间限制
2 s
内存限制
512 MB
标签
2-SAT
构造
DFS 及类似
并查集
图论
贪心
排序

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