A16291. Robot Queries
编程题
普及/提高-
知识点
题目描述
There is an infinite $2$ -dimensional grid. Initially, a robot stands in the point $(0, 0)$ . The robot can execute four commands:
- U — move from point $(x, y)$ to $(x, y + 1)$ ;
- D — move from point $(x, y)$ to $(x, y - 1)$ ;
- L — move from point $(x, y)$ to $(x - 1, y)$ ;
- R — move from point $(x, y)$ to $(x + 1, y)$ .
You are given a sequence of commands $s$ of length $n$ . Your task is to answer $q$ independent queries: given four integers $x$ , $y$ , $l$ and $r$ ; determine whether the robot visits the point $(x, y)$ , while executing a sequence $s$ , but the substring from $l$ to $r$ is reversed (i. e. the robot performs commands in order $s_1 s_2 s_3 \dots s_{l-1} s_r s_{r-1} s_{r-2} \dots s_l s_{r+1} s_{r+2} \dots s_n$ ).
- U — move from point $(x, y)$ to $(x, y + 1)$ ;
- D — move from point $(x, y)$ to $(x, y - 1)$ ;
- L — move from point $(x, y)$ to $(x - 1, y)$ ;
- R — move from point $(x, y)$ to $(x + 1, y)$ .
You are given a sequence of commands $s$ of length $n$ . Your task is to answer $q$ independent queries: given four integers $x$ , $y$ , $l$ and $r$ ; determine whether the robot visits the point $(x, y)$ , while executing a sequence $s$ , but the substring from $l$ to $r$ is reversed (i. e. the robot performs commands in order $s_1 s_2 s_3 \dots s_{l-1} s_r s_{r-1} s_{r-2} \dots s_l s_{r+1} s_{r+2} \dots s_n$ ).
输入格式
The first line contains two integers $n$ and $q$ ( $1 \le n, q \le 2 \cdot 10^5$ ) — the length of the command sequence and the number of queries, respectively.
The second line contains a string $s$ of length $n$ , consisting of characters U, D, L and/or R.
Then $q$ lines follow, the $i$ -th of them contains four integers $x_i$ , $y_i$ , $l_i$ and $r_i$ ( $-n \le x_i, y_i \le n$ ; $1 \le l \le r \le n$ ) describing the $i$ -th query.
The second line contains a string $s$ of length $n$ , consisting of characters U, D, L and/or R.
Then $q$ lines follow, the $i$ -th of them contains four integers $x_i$ , $y_i$ , $l_i$ and $r_i$ ( $-n \le x_i, y_i \le n$ ; $1 \le l \le r \le n$ ) describing the $i$ -th query.
输出格式
For each query, print YES if the robot visits the point $(x, y)$ , while executing a sequence $s$ , but the substring from $l$ to $r$ is reversed; otherwise print NO.
输入输出样例
输入 #1
8 3 RDLLUURU -1 2 1 7 0 0 3 4 0 1 7 8
输出 #1
YES YES NO
输入 #2
4 2 RLDU 0 0 2 2 -1 -1 2 3
输出 #2
YES NO
输入 #3
10 6 DLUDLRULLD -1 0 1 10 -1 -2 2 5 -4 -2 6 10 -1 0 3 9 0 1 4 7 -3 -1 5 8
输出 #3
YES YES YES NO YES YES
说明/提示
In the first query of the first sample, the path of the robot looks as follows:
In the second query of the first sample, the path of the robot looks as follows:
In the third query of the first sample, the path of the robot looks as follows:

In the second query of the first sample, the path of the robot looks as follows:
In the third query of the first sample, the path of the robot looks as follows:
