HALF-GCD 算法的阐述
翻了各课件,发现......
某个英文网站 是这么说的:
There is a way to calculate the GCD and resultants in $O(n\log^2n)$. To do this you should note that if you consider $a(x)=a_0+x^ka_1$ and $b(x)=b_0+x^kb_1$ where $k=\min(\deg a,\deg b)/2$ then basically the first few operations of Euclidean algorithm on $a(x)$ and $b(x)$