#include <iostream>
using namespace std;
int main()
{
int qu, num1, num2, max, lcm, n = 0,t=0;
cin >> qu >> num1 >> num2;
max = (num1 > num2) ? num1 : num2;
while (true)
{
if (max % num1 == 0 && max % num2 == 0)
{
lcm = max;
break;
}
else
max++;
}
n = max / num1 + max / num2;
t = qu / n * max;
qu -= qu / n;
cout << t;
return 0;
}