hdu1575:Tr A_矩陣的冪&二分求冪

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

二維矩陣做參數，寫在結構體裏，優化；

#include <stdio.h>
#include <string.h>

struct Matrix  
{
	int m[12][12];
}a,b,c;

int n,m,i,j,k;
Matrix deal(Matrix a,Matrix b)           //基本的矩陣乘法
{
    Matrix c;
	for (i=0;i<n;i++)
	{
		for (j=0;j<n;j++)
		{
			c.m[i][j]=0;
			for (k=0;k<n;k++)
			{
				c.m[i][j]+=a.m[i][k]*b.m[k][j];
			}
			c.m[i][j]%=9973;
		}
	}
	return c;
}
Matrix pow(Matrix a,Matrix b)           //二分法求階乘
{
   while (m!=0)
   {
	   if (m%2==1)
	   {
		   b=deal(a,b);
	   }
	  m/=2;
	  a=deal(a,a);
   }
   return b;
}
int main()
{//freopen("D:\\1.txt","r",stdin);

  int t;
   while (scanf("%d",&t)!=EOF)
   {
	   while (t--)
	   {
		   scanf("%d%d",&n,&m);         //n階矩陣，m次方
           for (i=0;i<n;i++)
           {
			   for (j=0;j<n;j++)
			   {
                   scanf("%d",&a.m[i][j]);     //a是目標矩陣
				   if (i==j)
				   {
					   b.m[i][j]=1;            //b是單位矩陣
				   }
				   else
					   b.m[i][j]=0;
			   }
           }
           c=pow(a,b);
		   int ans=0;
		   for (i=0;i<n;i++)
		   {
              ans+=c.m[i][i];
		   }
		   printf("%d\n",ans%9973);
	   }
   }
   return 0;
}