#P4351. [CERC2015] Frightful Formula

[CERC2015] Frightful Formula

题目描述

A frightful matrix is a square matrix of order n where the first row and the first column are explicitly specified, while the other elements are calculated using a frightful formula which is, actually, a simple recursive rule.

Given two integer sequences l and t,both of size n,as well as integer parameters a,b and c,the frightful matrix F is defined as follows:

  • The first column of the matrix is the sequence l:
F[k,1]=lkF[k, 1] = lk
  • The first row of the matrix is the sequence t:
F[1,k]=tkF[1, k] = tk
  • Other elements are calculated using a recursive formula:
F[i,j]=aF[i,j1]+bF[i1,j]+cF[i,j]=a*F[i,j-1]+b*F[i-1,j]+c

Given a frightful matrix, find the value of the element F[n,n]F[n,n] modulo 106+310^6 +3.

输入格式

The first line contains four integers n, a, b and c (2≤n≤200000, 0≤ a, b, c≤10610^6) – the size of the matrix and the recursion parameters, as described in the problem statement.

The two following lines contain integers l1,...,ln and t1,...,tn, respectively (l1 = t1, 0≤lk, tk ≤106).

输出格式

Output a single integer – the value of F[n,n]F[n,n] modulo 106+310^6 +3.

题目大意

定义一个矩阵 FF,其中第一行和第一列是给定的,计算矩阵方法如下:

矩阵的第一列是序列 ll

F[k,1]=F[k,1]= lkl _ k

矩阵的第一行是序列 tt

F[1,k]=F[1,k]= tkt _ k

其他元素使用给定的递归公式进行计算:

F[i,j]=a×F[i,j1]+b×F[i1,j]+cF[i,j]=a \times F[i,j-1]+b \times F[i-1,j]+c

现在要求找求出 F[n,n]F[n,n]106+310^6+3 的值。

输入输出格式。

输入格式:

第一行包含四个整数 nnaabbc(2n200000,0a,bc(2 \le n \le 200000,0 \le a,bc106)c \le 10^6) 矩阵的大小和递归参数,如问题描述中所述。

下面两行分别包含整数 l1,,lnl_1, \cdots ,l_nt1,,tn(l1=t1,0lk,tk106)t_1, \cdots ,t_n(l_1=t_1,0 \le lk,tk \le 10^6)

输出格式:

输出一个整数的值即 F[n,n]F[n,n]106+310^6+3

感谢 @ 守望提供的翻译。

3 0 0 0 
0 0 2 
0 3 0
0
4 3 5 2 
7 1 4 3 
7 4 4 8
41817

提示

Central Europe Regional Contest 2015 Problem F