#include <iostream>

using namespace std;

int main()
{
    long long n,m,t;cin>>n>>m>>t;
    long long l=1,r=1e18,ans=0;
    while(l<=r){
        long long mid=(l+r)/2;
        if(mid/m+mid/t>=n){
            ans=mid;
            r=mid-1;
        }
        else{
            l=mid+1;
        }
    }
    cout<<ans;

    return 0;
}