定理:gcd(a,b)*lcm(a,b)=a*b;
更相损减术:gcd(a,b)=gcd(b,a-b)=gcd(a,a-b)
欧几里得算法:gcd(a,b)=gcd(b,a mod b)
复杂度O(log(a+b))
转载于:https://www.cnblogs.com/zsben991126/p/10232621.html