1. 程式人生 > >E. Magic Stones CF 思維題

E. Magic Stones CF 思維題

boa ios mem ber its 思路 lec cin cif

E. Magic Stones time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output

Grigory has nn magic stones, conveniently numbered from 11 to nn . The charge of the ii -th stone is equal to cici .

Sometimes Grigory gets bored and selects some inner stone (that is, some stone with index

ii , where 2in?12≤i≤n?1 ), and after that synchronizes it with neighboring stones. After that, the chosen stone loses its own charge, but acquires the charges from neighboring stones. In other words, its charge cici changes to ci=ci+1+ci?1?cici′=ci+1+ci?1?ci .

Andrew, Grigory‘s friend, also has n

n stones with charges titi . Grigory is curious, whether there exists a sequence of zero or more synchronization operations, which transforms charges of Grigory‘s stones into charges of corresponding Andrew‘s stones, that is, changes cici into titi for all ii ?

Input

The first line contains one integer

nn (2n1052≤n≤105 ) — the number of magic stones.

The second line contains integers c1,c2,,cnc1,c2,…,cn (0ci2?1090≤ci≤2?109 ) — the charges of Grigory‘s stones.

The second line contains integers t1,t2,,tnt1,t2,…,tn (0ti2?1090≤ti≤2?109 ) — the charges of Andrew‘s stones.

Output

If there exists a (possibly empty) sequence of synchronization operations, which changes all charges to the required ones, print "Yes".

Otherwise, print "No".

Examples Input Copy
4
7 2 4 12
7 15 10 12
Output Copy
Yes
Input Copy
3
4 4 4
1 2 3
Output Copy
No
Note

In the first example, we can perform the following synchronizations (11 -indexed):

  • First, synchronize the third stone [7,2,4,12][7,2,10,12][7,2,4,12]→[7,2,10,12] .
  • Then synchronize the second stone: [7,2,10,12][7,15,10,12][7,2,10,12]→[7,15,10,12] .

In the second example, any operation with the second stone will not change its charge.

思路:

註意看題目給出的公式

c[i]‘=c[i+1]+c[i-1]-c[i]

可以變形成

c[i+1]-c[i]‘=c[i]-c[i-1]

c[i]‘-c[i-1]=c[i+1]-c[i]

這樣看來就是將第i項左右差分交換,可以把這個看成一種排序

所以將差分全部重新排序之後,如果上下差分都相同,則滿足題目要求

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <algorithm>
using namespace std;
typedef long long ll;
const int maxn=1e5+10;
ll a[maxn],b[maxn],c[maxn],d[maxn];
int main()
{
    int n;
    cin>>n;
    for(int i=1;i<=n;i++) scanf("%I64d",&a[i]);
    for(int i=1;i<=n;i++) scanf("%I64d",&b[i]);
    for(int i=1;i<n;i++)
    {
        c[i]=a[i+1]-a[i];
        d[i]=b[i+1]-b[i];
    }
    sort(c+1,c+n);
    sort(d+1,d+n);
    if(a[1]!=b[1]||a[n]!=b[n])
    {
        printf("No\n");
        return 0;
    }
    for(int i=1;i<n;i++)
    {
        if(c[i]!=d[i])
        {
            printf("No\n");
            return 0;
        }
    }
    printf("Yes\n");
    return 0;
}

  

E. Magic Stones CF 思維題