摘要：
真好用... 把系数相乘看成$(a M+b) (c M+d)=a c M^2+(a d+b c) M+b d$的形式,这样FFT的精度就够用了... C++ include include include define LL long long using namespace std; define 阅读全文
摘要：
贴个模板... C++ include include define LL long long using namespace std; const int maxn=2100005,tt=998244353; int n,m,a[maxn],b[maxn],re[maxn]; int qsm(in 阅读全文