因为太菜了才发在灌水区的...

#include <iostream>
using namespace std;

int main()
{	
	long long a,b,c,d;
	cin >> a >> b;
	long long maxn = max(a,b);
	long long minn = min(a,b);
	while(c > 0)
	{
		c = maxn%minn;
		d = maxn/minn;
		maxn = minn;
		minn /= d;
	}
	cout << maxn << " ";
	for(long long i=1;i<=a*b;i++)
	{
		if(i%a == 0 && i%b == 0)
		{
			cout << i;
			return 0;
		}
	}

	return 0;
}

20分，然后TLE,巨佬求