// (a+bi)(a+bi) = (a*a - b*b) + 2ab*i
void power2(int32_t a, int32_t b, int64_t k, int32_t m)
{
Complex x(a,b,m);
int64_t n = k;
while ((n & 1) == 0) {
x.square();
n >>= 1;
}
Complex P = x;
n >>= 1;
while (n > 0) {
x.square();
if ((n & 1) != 0)
P.multiply(x);
n >>= 1;
}
cout << P << endl;
}
void Complex::power(int n) {
Complex tmp = *this;
for (int i = 0; i < n; i++)
tmp.multiply(*this);
*this = tmp;
}
