Go: package main
import (
	"os"
	"fmt"
	"strconv"
	"bufio"
	"strings"
)

var sc = bufio.NewScanner(os.Stdin)
var out = bufio.NewWriter(os.Stdout)

func main(){
	sc.Split(bufio.ScanLines)
	defer out.Flush()

	for sc.Scan(){
		a, b := nextInts()
		x, y := gcd(a, b), lcm(a, b)
		fmt.Fprintf(out, "%d %d\n", x, y)
	}

}

func nextInts()(a, b int){
	s := strings.Split(sc.Text(), " ")
	ra, _ := strconv.Atoi(s[0])
	rb, _ := strconv.Atoi(s[1])
	a = ra
	b = rb
	return
}

func gcd(x, y int) int{
	if x<y{
		gcd(y, x)
	}
	for 0<y{
		r := x%y
		x, y = y, r
	}
	return x
}

func lcm(x, y int)int{
	return (x*y)/gcd(x, y)
}

C++: /* 2012-07-08T09:04:13 */
#define DEBUG_ON
#define CONDITION true
using namespace std;/*{{{*/

#include <algorithm>
#include <cassert>
#include <cctype>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <sys/time.h>
#include <vector>

#define INF (1e9)
static const double PI (3.14159265358979323846);
static const double EPS (1e-10);

typedef long long int ll;
typedef unsigned long long int ull;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef complex<double> P;

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
inline double now(){ struct timeval tv; gettimeofday(&tv, NULL); return ((double)(tv.tv_sec) + (double)(tv.tv_usec) * 1e-6); }

#define FOR(i, b, e) for (typeof(b) i = (b); assert((i) <= (e)), i != (e); ++i)
#define REP(i, n) FOR(i, 0, n)

#define IFC(c) if(c) continue;
#define IFB(c) if(c) break;
#define IFR(c, r) if(c) return r;

#define OPOVER(_op, _type) inline bool operator _op (const _type &t) const

#define arrsz(a) ( sizeof(a) / sizeof(a[0]) )

#define F first
#define S second
#define MP(a, b) make_pair(a, b)

#define SZ(a) ((ll)a.size())
#define PB(e) push_back(e)
#define SORT(v) sort((v).begin(), (v).end())
#define RSORT(v) sort((v).rbegin(), (v).rend())

#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define EACH(c,it) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define EXIST(s,e) ((s).find(e)!=(s).end())

#define BIT(n) (1ULL << (n))
#define BITOF(n, m) ((n) >> (m) & 1)

#define RANGE(a, b, c) ((a) <= (b) && (b) <= (c))

#ifdef DEBUG_ON
#define dprt(fmt, ...) if (CONDITION) fprintf(stderr, fmt, __VA_ARGS__)
#define darr(a) if (CONDITION) copy( (a), (a) + arrsz(a), ostream_iterator<int>(cerr, " ") ); cerr << endl
#define darr_range(a, f, t) if (CONDITION) copy( (a) + (f), (a) + (t), ostream_iterator<int>(cerr, " ") ); cerr << endl
#define dvec(v) if (CONDITION) copy( ALL(v), ostream_iterator<int>(cerr, " ") ); cerr << endl
#define darr2(a, n, m) if (CONDITION) FOR(i, 0, (n)){ darr_range( (a)[i], 0, (m) ); }
#define dvec2(v) if (CONDITION) FOR(i, 0, SZ(v)){ dvec( (v)[i] ); }
#define WAIT() if (CONDITION) { string _wait_; cerr << "(hit return to continue)" << endl; getline(cin, _wait_); }
#else
#define cerr if(0) cerr
#define dprt(fmt, ...)
#define darr(a)
#define darr_range(a, f, t)
#define dvec(v)
#define darr2(a, n, m)
#define dvec2(v)
#define WAIT()
#endif
/*}}}*/

ll lcm(ll a, ll b)
{
	if (a < b) {
		swap(a, b);
	}
	ll am = a, bm = b;
	while (true) {
		bm += b;
		if (am == bm) {
			return am;
		}
		if (bm > am) {
			swap(a, b);
			swap(am, bm);
		}
	}
}

ll gcd(ll a, ll b)
{
	if (a < b) {
		swap(a, b);
	}
	while (true) {
		if (a % b == 0) {
			return b;
		}
		ll buf = a;
		a = b;
		b = buf % b;
	}
}

int main(int argc, char const* argv[])
{
	ll a, b;
	cin >> a >> b;
	cout << gcd(a, b) << " " << lcm(a, b) << endl;
	return 0;
}

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;
}