uva 11149 矩阵快速幂 求矩阵1-n次幂的和

#include<cstdio>#include<cstring>#define mod 10using namespace std;int n;struct matrix{int d[50][50];};matrix add(matrix a,matrix b){matrix c;memset(c.d,0,sizeof(c.d));for(int i=0;i<n;i++)for(int j=0;j<n;j++)c.d[i][j]=(a.d[i][j]+b.d[i][j])%mod;return c;}matrix mutl(matrix a,matrix b){matrix c;for(int i=0;i<n;i++)for(int j=0;j<n;j++){c.d[i][j]=0;for(int k=0;k<n;k++)c.d[i][j]=(c.d[i][j]+a.d[i][k]*b.d[k][j])%mod;}return c;}matrix qcal(matrix a,int k){matrix res;for(int i=0;i<n;i++)for(int j=0;j<n;j++)if(i==j) res.d[i][j]=1;else res.d[i][j]=0;while(k){if(k&1)res=mutl(res,a);k>>=1;a=mutl(a,a);}return res;}matrix solve(matrix a,int k){if(k==1)return a;matrix t=solve(a,k/2);matrix res=add(t,mutl(t,qcal(a,k/2)));if(k&1)res=add(res,qcal(a,k));return res;}int main(){int k;while(scanf("%d%d",&n,&k)==2 && n){matrix t;for(int i=0;i<n;i++)for(int j=0;j<n;j++){scanf("%d",&t.d[i][j]);t.d[i][j]%=10;}t=solve(t,k);for(int i=0;i<n;i++){printf("%d",t.d[i][0]);for(int j=0;j<n;j++)printf(" %d",t.d[i][j]);printf("\n");}printf("\n");}}