POJ 2118 Firepersons 线性递推 矩阵快速幂

#include <cstdio>
#include <algorithm>
#include <vector>

using namespace std;

typedef long long ll;
typedef vector<ll> vec;
typedef vector<vec> mat;

const int MOD = 10000;

mat mul(mat & A, mat &B)
{
mat C(A.size(), vec(B[0].size()));
for (int i = 0; i < A.size(); ++i)
for (int k = 0; k < B.size(); k++)
for (int j = 0; j < B[0].size(); ++j)
C[i][j] = (C[i][j] + A[i][k] * B[k][j]) % MOD;
return C;
}
mat pow(mat A, ll n)
{
mat B(A.size(), vec(A.size()));
for (int i = 0; i < A.size(); ++i)
B[i][i] = 1;
while (n){
if (n & 1) B = mul(B, A);
A = mul(A, A);
n >>= 1;
}
return B;
}

ll K,N;

int main(void)
{
//freopen("input.txt","r",stdin);
while(scanf("%lld",&K),K){
mat A(K,vec(K));
mat B(K,vec(1));
for(int i = 0; i < K; ++i)
scanf("%lld",&B[K - 1 - i][0]);
for(int i = 0; i < K; ++i)
scanf("%lld",&A[0][i]);
for(int i = 1; i < K; ++i)
A[i][i-1] = 1;
scanf("%lld",&N);
if(N < K)
printf("%lld\n",B[K - 1 - N][0]);
else{
A = pow(A,N - K + 1);
B = mul(A,B);
printf("%lld\n",B[0][0]);
}
}
return 0;
}