最大公约数gcd，最小公倍数lcm

 1 #include<iostream>
 2 #include<cstdio>
 3 using namespace std;
 4 
 5 int x,y;
 6 
 7 int gcd(int a,int b){
 8     if(b==0) return a;
 9     return gcd(b,a%b);
10 }
11 
12 int lcm(int a,int b){
13     return a*b/gcd(a,b);
14 }
15 
16 int main(){
17     cin>>x>>y;
18     cout<<gcd(x,y)<<endl;
19     cout<<lcm(x,y)<<endl;
20     return 0;
21 }