Codeforces761B Dasha and friends 2017-02-05 23:34 162人阅读 评论(0) 收藏

B. Dasha and friends

time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Running with barriers on the circle track is very popular in the country where Dasha lives, so no wonder that on her way to classes she saw the following situation:

The track is the circle with length L, in distinct points of which there are n barriers.
Athlete always run the track in counterclockwise direction if you look on him from above. All barriers are located at integer distance from each other along the track.

Her friends the parrot Kefa and the leopard Sasha participated in competitions and each of them ran one lap. Each of the friends started from some integral point on the track. Both friends wrote the distance from their start along the track to each of the n barriers.
Thus, each of them wrote n integers in the ascending order, each of them was between 0 and L - 1,
inclusively.

Consider
an example. Let L = 8, blue points are barriers, and green points are Kefa's start (A) and Sasha's start (B). Then Kefa writes down
the sequence[2, 4, 6], and Sasha writes down [1, 5, 7].

There are several tracks in the country, all of them have same length and same number of barriers, but the positions of the barriers can differ among different tracks. Now Dasha is interested if it is possible that Kefa and Sasha ran the same track or they
participated on different tracks.

Write the program which will check that Kefa's and Sasha's tracks coincide (it means that one can be obtained from the other by changing the start position). Note that they always run the track in one direction — counterclockwise, if you look on a track from
above.

Input

The first line contains two integers n and L (1 ≤ n ≤ 50, n ≤ L ≤ 100)
— the number of barriers on a track and its length.

The second line contains n distinct integers in the ascending order — the distance from Kefa's start to each barrier in the order of
its appearance. All integers are in the range from 0 to L - 1 inclusively.

The second line contains n distinct integers in the ascending order — the distance from Sasha's start to each barrier in the order
of its overcoming. All integers are in the range from 0 to L - 1 inclusively.

Output

Print "YES" (without quotes), if Kefa and Sasha ran the coinciding tracks (it means that the position of all barriers coincides, if they start running from
the same points on the track). Otherwise print "NO" (without quotes).

Examples

input

3 8
2 4 6
1 5 7

output

YES

input

4 9
2 3 5 8
0 1 3 6

output

YES

input

2 4
1 3
1 2

output

NO

Note

The first test is analyzed in the statement.

——————————————————————————————————————————————————————————————————

题目的意思是有两个人站在一个环上不同的位置记录前方的点到自己的距离，有没有可能存在一个换符合条件

不管人怎么站，每个点之间差值一定一样，随意算出差值然后枚举遍历是否相同。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <string>
#include <queue>
#include <vector>
#include <stack>
#include <set>
#include <map>
using namespace std;
#define INF 0x3f3f3f3f
#define MAXN 100005

int a[1000],b[1000];
int x[1000],y[1000];
int l,n;
int main()
{
  while(~scanf("%d%d",&n,&l))
  {
      for(int i=0;i<n;i++)
      scanf("%d",&a[i]);
      for(int i=0;i<n-1;i++)
        x[i]=a[i+1]-a[i];
      x[n-1]=a[0]+l-a[n-1];

      for(int i=0;i<n;i++)
      scanf("%d",&b[i]);
      for(int i=0;i<n-1;i++)
        y[i]=b[i+1]-b[i];
      y[n-1]=b[0]+l-b[n-1];
      int fl=0;
      for(int i=0;i<n;i++)
      {
          int flag=0;
          for(int j=0;j<n;j++)
          {
              int xx=j;
              int yy=j+i;
              if(yy>=n)
                yy-=n;
              if(x[xx]!=y[yy])
              {
                  flag=1;
                  break;
              }
          }
          if(flag==0)
          {
              fl=1;
              break;
          }
      }
      if(fl==1)
        printf("YES\n");
        else
        printf("NO\n");

  }
    return 0;
}