Score : $300$ points
There are $N$ people in an $xy$-plane. Person $i$ is at $(X_i, Y_i)$. The positions of all people are different.
We have a string $S$ of length $N$ consisting of L
and R
.
If $S_i =$ R
, Person $i$ is facing right; if $S_i =$ L
, Person $i$ is facing left. All people simultaneously start walking in the direction they are facing. Here, right and left correspond to the positive and negative $x$-direction, respectively.
For example, the figure below shows the movement of people when $(X_1, Y_1) = (2, 3), (X_2, Y_2) = (1, 1), (X_3, Y_3) =(4, 1), S =$ RRL
.
We say that there is a collision when two people walking in opposite directions come to the same position. Will there be a collision if all people continue walking indefinitely?
L
and R
.Input is given from Standard Input in the following format:
$N$ $X_1$ $Y_1$ $X_2$ $Y_2$ $\vdots$ $X_N$ $Y_N$ $S$
If there will be a collision, print Yes
; otherwise, print No
.
3 2 3 1 1 4 1 RRL
Yes
This input corresponds to the example in the Problem Statement.
If all people continue walking, Person $2$ and Person $3$ will collide. Thus, Yes
should be printed.
2 1 1 2 1 RR
No
Since Person $1$ and Person $2$ walk in the same direction, they never collide.
10 1 3 1 4 0 0 0 2 0 4 3 1 2 4 4 2 4 4 3 3 RLRRRLRLRR
Yes