hdu1575 Tr A (矩阵快速幂)

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1575

#include <stdio.h>
#include <string.h>
#define MAXN 11
#define MOD 9973

typedef struct Matrix
{
	int matr[MAXN][MAXN];
}Matrix;

int n;
Matrix init,unit,c;

Matrix MatrixMult(Matrix a,Matrix b)
{
	int i,j,k;
	for (i=0;i<n;++i)
	{
		for(j=0;j<n;++j)
		{
			c.matr[i][j]=0;
			for(k=0;k<n;++k)
				c.matr[i][j]+=(a.matr[i][k]*b.matr[k][j])%MOD;
			c.matr[i][j]%=MOD;
		}
	}
	return c;
}

int pow_mod(int x)
{
	int i,sum=0;
	while(x)
	{
		if(x&1)
			unit=MatrixMult(unit,init);
		init=MatrixMult(init,init);
		x>>=1;
	}
	for(i=0;i<n;++i)
		sum=(sum+unit.matr[i][i])%MOD;
	return sum%MOD;
}

int main()
{
	int test,ans,i,j,k;
	scanf("%d",&test);
	while(test--)
	{
		scanf("%d %d",&n,&k);
		for(i=0;i<n;++i)
		{
			for(j=0;j<n;++j)
			{
				scanf("%d",&init.matr[i][j]);
				unit.matr[i][j]=0;
			}
			unit.matr[i][i]=1;//unit单位矩阵
		}
		ans=pow_mod(k);
		printf("%d\n",ans);
	}
	return 0;
}