Go: package main

import "fmt"

func main() {
	var a, b int
	var gcd, lcm int

	for {
		_, err := fmt.Scanf("%d %d", &a, &b)
		if err != nil {
			return
		}

		var big, small int
		// GCD
		if a > b {
			big = a
			small = b
		} else {
			big = b
			small = a
		}

		for {
			if big%small == 0 {
				gcd = small
				break
			} else {
				small, big = big%small, small
			}
		}

		// LCM
		lcm = a * b / gcd

		fmt.Println(gcd, lcm)
	}
}

C++: 
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#include <stdio.h>
   
int main(){
    
    int buf1[50],buf2[50];
    
    int k = 0;
    while( scanf( "%d %d",&buf1[k],&buf2[k] ) != EOF ) k++;
    
    for( int i = 0;i < k;i++ ){
        int b1 = buf1[i],b2 = buf2[i];
        int m,n;
        if( b1< b2 ){
            m = b2,n = b1;
        } else if( b1 > b2 ){
            m =  b1,n = b2;
        } else {
            n = 0;
            m = b1;
        }
         
        while( n != 0 ){
            int buf = n;
            n = m % n;
            m = buf;
        }
        printf( "%d ",m );
 
        while( b1 != b2 ){
            if( b1 < b2 ) b1 += buf1[i];
            else             b2 += buf2[i];
        }
        printf( "%d\n",b1 );
    }
    return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<ll> VL;
typedef vector<VL> VVL;
typedef pair<int, int> PII;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()
#define MP make_pair
#define PB push_back
#define MOD 1000000007
#define INF (1LL<<30)
#define LLINF (1LL<<60)
#define PI 3.14159265359
#define EPS 1e-12
#define int ll

int gcd(int a, int b) {
  return b != 0 ? gcd(b, a%b) : a;
}
int lcm(int a, int b) {
  return a*b/gcd(a, b);
}

signed main(void)
{
  int a, b;
  while(cin >> a >> b) {
    cout << gcd(a, b) << " " << lcm(a, b) << endl;
  }

  return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define ll long long
#define REP(i,n) for(int i=0;i<n;i++)
#define PP(m) REP(i, m.size()) cout << m[i] << endl;

int gcd(int a, int b) {
    if(b == 0) return a;
    return gcd(b, a % b);
}

int lcm(int a, int b) {
    return a / gcd(a, b) * b ;
}

int main() {
  int a,b;
  while (cin >> a >> b && a) {
    cout << gcd(a,b) << " " << lcm(a,b) << endl;
  }

  return 0;
}

C++: #include<cstdio>
long gcd(long a,long b){
    if(a<b){
        long t=a;
        a=b;
        b=t;
    }
    while(b!=0){
        long t=a;
        a=b;
        b=t%b;
    }
    return a;
}
int main(){
    int a,b;
    while(~scanf("%d%d",&a,&b)){
        long g=gcd(a,b);
        long l=a/g*b;
        printf("%ld %ld\n",g,l);
    }
}

C++: #include <iostream>
using namespace std;

int main()
{
	long long a, b, r, m;

	while (cin >> a >> b) {
		r = a % b;
		m = a * b;

		while (r > 0) {
			a = b;
			b = r;
			r = a % b;
		}

		cout << b << " " << m / b << endl;
	}

	return 0;
}

C++: #include <iostream>
using namespace std;

long gcd(int a,int b){
	if(a == 0)return b;
	else if(a > b)return gcd(a%b,b);
	return gcd(b%a,a);
}

int main(){
	long a,b;
	while(!cin.eof()){
		cin >> a >> b;
		long g = gcd(a,b);
		cout << g << " " << a*(b/g);
	}
	return 0;
}

C++: #include <iostream>
using namespace std;
typedef long long LL;
LL gcd(LL a, LL b) {return b?gcd(b, a%b):a; }

int main()
{
    LL a, b;
    while(cin>>a>>b)
    {
        LL t = gcd(a, b);
        cout<<t<<" "<<a/t*b<<endl;
    }
    return 0;
}

C++: #include<iostream>
using namespace std;

int GCD(int n,int m){if(n%m==0)return m;return GCD(m,n%m);}

int main(){
	std::ios::sync_with_stdio(false);
    std::cin.tie(0);
	
	int n[50]={0};
	int i=0;
	while(cin>>n[i++]);
	int nn=i-1;
	int gcd=0,lcm=0,a=0,b=0;
	for(int j=0;j<nn;j+=2){
		gcd=GCD(n[j],n[j+1]);
		a=n[j]/gcd,b=n[j+1]/gcd;
		cout<<gcd<<" "<<gcd*a*b<<endl;
	}
	return 0;
}

C++: #include <iostream>

//a>bのときの最大公約数(greatest common divisor)を計算する関数
long int get_gcd(long int a, long int b){
    long int r,gcd;
	r = a % b;
	if(r == 0)
		gcd = b;
	else 
		gcd = get_gcd(b,r);
    return gcd;
}
			

int main(){
	long int a, b,tmp,gcd;
	while(std::cin >> a >> b){
		if(b>a){
		tmp = a;
		a = b;
		b = tmp;
	}
		gcd = get_gcd(a,b);
		std::cout << gcd << " " << a*b/gcd << std::endl;
	}
	return 0;
}

C++: #include<algorithm>
#include<functional>
#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<string>
#include<sstream>
#include<iostream>
#include<iomanip>
#include<vector>
#include<list>
#include<stack>
#include<queue>
#include<map>
#include<set>
#include<bitset>

#define all(c) (c).begin(), (c).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define pb(e) push_back(e)
#define mp(a, b) make_pair(a, b)
#define fr first
#define sc second

typedef unsigned long long ull;
typedef long long ll;

const int INF=100000000;
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};

using namespace std;

typedef pair<int ,int > P;

int n,m;

int gcd(int a,int b)
{
	if(b==0) return a;
	return gcd(b,a%b);
}
int lcm(int a,int b)
{
	return a/gcd(a,b)*b;
}

int main()
{
	while(cin>>n>>m)
	{
		cout<<gcd(n,m)<<" "<<lcm(n,m)<<endl;
	}

	return 0;
}

C++: #include <cstdio>
int gcd(int a,int b)
{
    return b? gcd(b,a%b):a;
}
int main()
{
    int a,b;
    while(scanf("%d%d",&a,&b) != EOF)
    {
        int g = gcd(a,b);
        int l = a/g*b;
        printf("%d %d\n",g,l);
    }
}

C++: #include <iostream>
using namespace std;
int main() 
{
    long a, b, c, d, tmp;
    while (std::cin >> a >> b) {
    	d = a * b;
		if(a < b) {
            tmp = a;
            a = b;
            b = tmp;
        }
 
    c = a % b;
    while(c != 0) {
        a = b;
        b = c;
        c = a % b;
    }
    cout << b << " " << d / b << endl;
    }
       return 0;
}

C++: #include <stdio.h>

int main(){
	int a,b,gcd,lcm,status,temp;
	while(1){
		status=scanf("%d%d",&a,&b);
		
		if (status==EOF) break;
		
		if (a>b){
			temp=b;
			b=a;
			a=temp;
		}
		
		gcd=a;
		
		while(gcd%b!=0){
				gcd+=a;
		}
		
		lcm=(int)(1.0*a*b/gcd);
		
		if (a*b==gcd)lcm=1;
		if (a==gcd) lcm=b;

		printf ("%d %d\n",lcm,gcd);
	}
	return 0;
}

C++: #include <iostream>
using namespace std;

int Func_gcd(int num1, int num2){
	int surplus;
	
	if(!num2){
		return num1;
	}
			
	while((surplus=num1%num2) != 0){
		num1 = num2;
		num2 = surplus;
	}
	
	return num2;
}

int main()
{
    int gcd, lcm;
	int num1, num2;
	
	while(cin>>num1>>num2){
		gcd = Func_gcd(num1, num2);
		lcm = (num1*num2)/gcd;
				
		cout << gcd << " " << lcm << "\n";
	}
	
	return 0;
}

C++: #include <iostream>

using namespace std;

int main(int argc, char **argv)
{
	int a, b, s, t;
	
	while(cin >> a >> b){
		for(int i = (a > b)? b : a; i >= 1; i--){
			if(b%i == 0 && a%i == 0){
				cout << i << " ";
				break;
			}
		}
		s = a;
		t = b;
		while(s != t){
			if(s > t){
				t += b;
			} else {
				s += a;
			}
		}
		cout << s << endl;
	}
	
	return 0;
}

C++: #include<iostream>
#include<algorithm>
using namespace std;
int gcd(int,int);
int lcm(int,int);
int tes(int,int);

int main(){
  int a,b;
  while(cin >> a >> b){
    cout << gcd(a,b);
    cout << " " << lcm(a,b) << endl;
  }
}

int gcd(int a,int b){
  int n;
  while(a!=b)
    {
      if(a>b)a=a-b;
      else{b=b-a;}
    }
  return a;
}
/*
int tes(int a,int b){
  if(b == 0)return a;
  return tes(b,a%b);
}
*/

int lcm( int a,int b){
  return (a*b)/gcd(a,b);
}

C++: #include<cstdio>
typedef unsigned long long ll;
int gcd(int a,int b)
{
	if(b==0)return a;
	else return gcd(b,a%b);
}
int main()
{
	ll n,m;
	while(scanf("%d%d",&n,&m)==2)
	{
		ll d = gcd(n,m),ans = n*m/d;
		printf("%lld %lld\n",d,n*m/d);
	}
	return 0;
}