```cpp
# include <iostream>
# define ll long long
using namespace std;
int n;
const int mod = 1e9 + 7;
struct Matrix{
ll m[101][101];
};
Matrix a;
Matrix mul(Matrix x, Matrix y){
Matrix re;
for (int i = 1; i <= n; i++)
for (int j = 1; j <= n; j++){
for (int k = 1; k <= n; k++)
re.m[i][j] += x.m[i][k] * y.m[k][j];
re.m[i][j] %= mod;
}
return re;
}
Matrix ksm(int k, Matrix x){
Matrix ret;
for (int i = 1; i <= n; i++)
for (int j = 1; j <= n; j++)
if (i == j)
ret.m[i][j] = 1;
else
ret.m[i][j] = 0;
while (k){
if (k & 1)
ret = mul(ret, x);
k = k >> 1;
x = mul(x, x);
}
return ret;
}
void print(Matrix m){
for (int i = 1; i <= n; i++){
for (int j = 1; j <= n; j++)
cout << m.m[i][j] << ' ';
cout << endl;
}
}
int main(){
int k;
cin >> n >> k;
for (int i = 1; i <= n; i++)
for (int j = 1; j <= n; j++)
cin >> a.m[i][j];
print(ksm(k, a));
return 0;
}
```
谢谢帮调，感激不尽。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:02:37
初步判断是全输出了 $0$。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:04:15
`x.m[i][k] * y.m[k][j]` 加个取模。
否则最大数可达 $(10^9+6)^2 \times n$。
by CuiZhenhang @ 2022-12-06 15:04:53
@[CuiZhenhang](/user/561644) 好的，谢谢，我去试试。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:05:37
@[CuiZhenhang](/user/561644) 貌似不行。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:06:21
`mul` 函数中的 `re` 没有初始清空。
建议 `memset`。
by CuiZhenhang @ 2022-12-06 15:06:45
@[CuiZhenhang](/user/561644) 没用，还是输出 $0$。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:08:16
注意 $0 \le k \le 10^{12}$
by CuiZhenhang @ 2022-12-06 15:09:15
@[CuiZhenhang](/user/561644) 但这不至于造成全 WA 吧。应该至少有一个点是 $k=0$。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:11:19
@[CuiZhenhang](/user/561644) 过了，谢谢。关注了。
by Ja50nY0un9_as_AgNO3 @ 2022-12-06 15:12:06