有谁会高精乘法的吗

#include<iostream>
#define ull unsigned long long
using namespace std;
inline ull gcd(ull m,ull n){
    return n? gcd(n,m%n):m;
}
ull x,y;
int main(){
    cin>>x>>y;
    cout<<x/gcd(x,y)*y; 
    return 0;
}