1 | #include <bits/stdc++.h> |
2 | #define ll long long |
3 | |
4 | using namespace std; |
5 | |
6 | ll n, x, y; |
7 | |
8 | bool check(ll t) { |
9 | ll a = (t / x); |
10 | ll b = (t / y); |
11 | return (a + b >= n); |
12 | } |
13 | |
14 | int main() { |
15 | std::ios_base::sync_with_stdio(false); |
16 | cin.tie(0); |
17 | cout.tie(0); |
18 | cin >> n >> x >> y; |
19 | |
20 | ll low = 0, high = n * min(x, y), ans = high; |
21 | n--; |
22 | |
23 | while (low <= high) { |
24 | ll mid = (low + high) / 2; |
25 | if (check(mid)) { |
26 | ans = mid; |
27 | high = mid - 1; |
28 | } else { |
29 | low = mid + 1; |
30 | } |
31 | } |
32 | |
33 | cout << ans + min(x, y); |
34 | return 0; |
35 | } |
36 | |
37 | |
38 | |
39 | |
40 | |
41 | |