CF555D.Case of a Top Secret

普及/提高-

通过率:0%

AC君温馨提醒

该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。

题目描述

Andrewid the Android is a galaxy-famous detective. Now he is busy with a top secret case, the details of which are not subject to disclosure.

However, he needs help conducting one of the investigative experiment. There are nn pegs put on a plane, they are numbered from 11 to nn , the coordinates of the ii -th of them are (xi,0)(x_{i},0) . Then, we tie to the bottom of one of the pegs a weight on a tight rope of length ll (thus, its coordinates will be equal to (xi,l)(x_{i},-l) , where ii is the number of the used peg). Then the weight is pushed to the right, so that it starts to rotate counterclockwise. At the same time, if the weight during rotation touches some of the other pegs, it then begins to rotate around that peg. Suppose that each peg itself is very thin and does not affect the rope length while weight is rotating around it.

More formally, if at some moment the segment of the rope contains one or more pegs in addition to the peg around which the weight is rotating, the weight will then rotate around the farthermost one of them on a shorter segment of a rope. In particular, if the segment of the rope touches some peg by its endpoint, it is considered that the weight starts to rotate around that peg on a segment of the rope of length 00 .

At some moment the weight will begin to rotate around some peg, without affecting the rest of the pegs. Andrewid interested in determining the number of this peg.

Andrewid prepared mm queries containing initial conditions for pushing the weight, help him to determine for each of them, around what peg the weight will eventually rotate.

输入格式

The first line contains integers nn and mm ( 1<=n,m<=21051<=n,m<=2·10^{5} ) — the number of pegs and queries.

The next line contains nn integers x1,x2,...,xnx_{1},x_{2},...,x_{n} ( 109<=xi<=109-10^{9}<=x_{i}<=10^{9} ) — the coordinates of the pegs. It is guaranteed that the coordinates of all the pegs are distinct integers.

Next mm lines contain the descriptions of the queries of pushing the weight, each consists of two integers aia_{i} ( 1<=ai<=n1<=a_{i}<=n ) and lil_{i} ( 1<=li<=1091<=l_{i}<=10^{9} ) — the number of the starting peg and the length of the rope.

输出格式

Print mm lines, the ii -th line should contain the number of the peg around which the weight will eventually rotate after the ii -th push.

输入输出样例

  • 输入#1

    3 2
    0 3 5
    2 3
    1 8
    

    输出#1

    3
    2
    
  • 输入#2

    4 4
    1 5 7 15
    1 4
    2 15
    3 16
    1 28
    

    输出#2

    2
    4
    3
    1
    

说明/提示

Picture to the first sample test:

Picture to the second sample test:

Note that in the last query weight starts to rotate around the peg 1 attached to a rope segment of length 0.

首页