标签:als printf class cstring main size matrix scanf 注意
矩阵A乘矩阵B是A的第i行向量乘以B的第j列向量的值放在结果矩阵的i行j列。因为矩阵乘法满足结合律,所以它可以与一般的快速幂算法同理使用。注意矩阵在乘的时候取模。
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
#define ll long long
const int MAX_N = 110;
const ll P = 1e9 + 7;
struct Matrix
{
ll A[MAX_N][MAX_N];
int N;
Matrix(int n)
{
N = n;
memset(A, 0, sizeof(A));
}
void operator = (const Matrix& a)
{
memcpy(A, a.A, sizeof(a.A));
N = a.N;
}
void operator *= (const Matrix& a)
{
Matrix ans(N);
for (int i = 1; i <= N; i++)
for (int j = 1; j <= N; j++)
for (int k = 1; k <= N; k++)
ans.A[i][j] += (A[i][k] % P) * (a.A[k][j] % P) % P;
*this = ans;
}
void operator %= (const ll x)
{
for (int i = 1; i <= N; i++)
for (int j = 1; j <= N; j++)
A[i][j] %= x;
}
void SetAnsUnit()
{
memset(A, 0, sizeof(A));
for (int i = 1; i <= N; i++)
A[i][i] = 1;
}
bool Empty()
{
for (int i = 1; i <= N; i++)
for (int j = 1; j <= N; j++)
if (A[i][j])
return false;
return true;
}
void Print()
{
for (int i = 1; i <= N; i++)
{
for (int j = 1; j <= N; j++)
printf("%lld ", A[i][j]);
printf("\n");
}
}
};
Matrix Power(Matrix a, ll n)
{
Matrix ans(a.N);
ans.SetAnsUnit();
while (n)
{
if (n & 1)
{
ans *= a;
ans %= P;
}
a *= a;
a %= P;
n >>= 1;
}
return ans;
}
int main()
{
int n;
long long k;
scanf("%d%lld", &n, &k);
static Matrix a(n);
for (int i = 1; i <= n; i++)
for (int j = 1; j <= n; j++)
scanf("%d", &a.A[i][j]);
Power(a, k).Print();
return 0;
}
标签:als printf class cstring main size matrix scanf 注意
原文地址:https://www.cnblogs.com/headboy2002/p/9362888.html