#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef long double ld;
ll n, x, y, ans;

bool check(ll m)
{
    return m / x + m / y >= n - 1 && m >= 0;
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> x >> y;
    ll l = 0, r = n * max(x, y), m, ans = min(x, y);
    while (l < r)
    {
        m = (l + r) / 2;
        if (check(m - ans))
            r = m;
        else
            l = m + 1;
    }
    cout << r << endl;
    return 0;
}