蒟蒻求助

#include <bits/stdc++.h>
#define rep( i , l , r ) for( int i = (l) ; i <= (r) ; ++i )
#define per( i , r , l ) for( int i = (r) ; i >= (l) ; --i )
#define erep( i , u ) for( int i = head[(u)] ; ~i ; i = e[i].nxt )
using namespace std;
inline int _read(){
    register int x = 0 , f = 1;
    register char ch = getchar();
    while( ch > '9' || ch < '0' ) { if( ch == '-' ) f = -1; ch = getchar(); }
    while( ch >= '0' && ch <= '9' ){
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    return x * f;
}
typedef long long ll;
const int maxn = 100 + 5;
const ll MOD = 1000000007ll;
int N , K;
struct Mat {
    ll mat[maxn][maxn];
};
Mat operator * (Mat a, Mat b) {
    Mat c;
    memset(c.mat, 0, sizeof(c.mat));
    int i, j, k;
    for(k = 0; k < N; ++k) {
        for(i = 0; i < N; ++i) {
            if(a.mat[i][k] == 0) continue;   
            for(j = 0; j < N; ++j) {
                if(b.mat[k][j] == 0)  continue; 
                c.mat[i][j] = ( c.mat[i][j] + a.mat[i][k] * b.mat[k][j] ) % MOD;
            }
        }
    }
    return c;
}
Mat operator ^ (Mat a, int k) {
    Mat c;
    int i, j;
    for(i = 0; i < N; ++i)
        for(j = 0; j < N; ++j)
            c.mat[i][j] = (i == j);    

    for(; k; k >>= 1) {
        if( k & 1 ) c = c * a;
        a = a * a;
    }
    return c;
}
int main(){
    scanf("%d %d" , &N , &K);
    Mat a , b ;
    rep( i , 0 , N - 1 ) rep( j , 0 , N - 1 ) scanf("%d" , &a.mat[i][j]);
    b = a ^ K;
    rep( i , 0 , N - 1 ){
        rep( j , 0 , N - 2 )
            printf("%lld " , b.mat[i][j]);
        printf("%lld\n" , b.mat[i][N - 1]); 
    }
    return 0;
}