[Matrix Multiplication] [SSL 1530] Pebolaci Sequence III

[Matrix Multiplication] [SSL 1530] Pebolaci Sequence III

topic

Find the sequence $f[n]=f[n-1]+f[n-2]+1$ The first of$N$ items.$f$[1]=1,$f$[2]=1.

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enter

$n$ (1 ＜ 4n $ ＜ ２ ^ 31-1)

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Output

The first $N$ item result$mod$ 9973

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Sample

input
12345

output
8932

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Problem-solving ideas

This problem and this problem like
to pay more 1
to answer matrix plus a put a
high-risk matrix becomes ↓ to

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Code

#include<iostream>
#include<cstring> 
#include<cstdio>
using namespace std;
const int mo=9973;
long long n;
struct lzf{
    
    
	int n,m;
	long long h[5][5];
}a,b,x;
lzf operator *(lzf l,lzf y)
{
    
    
	x.n=l.n,x.m=y.m;
	memset(x.h,0,sizeof(x.h));
	for (int k=1;k<=l.m;k++)
	    for (int i=1;i<=x.n;i++)
		    for (int j=1;j<=x.m;j++) 
		        x.h[i][j]=(x.h[i][j]+l.h[i][k]*y.h[k][j]%mo)%mo;
	return x;
}
void power(long long n)
{
    
    
	 if (n & 1) a=a*b;
	 if (n==1) return;
	 b=b*b;
	 power(n/2);
}
int main()
{
    
    
	a.n=1,a.m=3;
	a.h[1][1]=a.h[1][2]=a.h[1][3]=1;
	b.n=3,b.m=3;
    b.h[1][2]=b.h[2][1]=b.h[2][2]=b.h[3][2]=b.h[3][3]=1;
	scanf("%lld",&n);
	power(n-1);
	printf("%lld",a.h[1][1]);
	return 0;
}