标签:#define mem fine matrix amp cpp 代码 IV scan
转移方程好写吧
一个一维递推式
然后我们可以构造矩阵优化
嗯,最近学一下递推优化
#include<cstdio>
#include<cstring>
#include<algorithm>
#define mod 7777777
int K,n;
#define LL long long
const int maxn = 11;
struct matrix {
int a[maxn][maxn];int c,r;
void in(int x,int y) {
r = x,c = y;
}
matrix() {
c = 0,r = 0;
memset(a,0,sizeof a); n = 0 ;
}
} ans,tmp;
matrix operator * (const matrix A,const matrix B) {
matrix ret; ret.in(A.r,B.c);
for(int i = 0; i < ret.r;++ i)
for(int j = 0;j < ret.c;++ j)
for(int k = 0;k < A.c;++ k)
ret.a[i][j] = (ret.a[i][j] + ((long long )A.a[i][k] * B.a[k][j] % mod) )% mod;
return ret;
}
int dp[maxn];
matrix pow(matrix a,int k) {
matrix ret;
ret.in(K,K);
for(int i = 0;i < K;++ i) ret.a[i][i] = 1;
for(;k;k >>= 1,a = a * a)
if(k & 1) ret = ret * a;
return ret;
}
int main() {
scanf("%d%d",&K,&n);
tmp.in(K,K);
for(int i = 0;i < K;++ i) tmp.a[i][0] = 1;
for(int i = 1;i < K;++ i) tmp.a[i - 1][i] = 1;
tmp = pow(tmp,n);
ans.in(1,K);
ans.a[0][0] = 1;
ans = ans * tmp;
printf("%lld\n",ans.a[0][0]);
return 0;
}
标签:#define mem fine matrix amp cpp 代码 IV scan
原文地址:https://www.cnblogs.com/sssy/p/9193818.html