#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define ALL(v) v.begin(),v.end()
typedef long long ll;

#include <bits/stdc++.h>
using namespace std;

int main(){
  ll a,b,k;
  cin>>a>>b>>k;
  
  if(a==b){
    cout<<a*k<<endl;
    return 0;
  }
  if(a>b) swap(a,b);
  if(b%a==0){
    cout<<a*k<<endl;
    return 0;
  }
  
  ll l=lcm(a,b);
  ll p=l/a+l/b-1;
  if(k%p==0){
    cout<<k/p*l<<endl;
    return 0;
  }

  ll ans=0;
  ans+=k/p*l;
  k-=k/p*p;
  
  if(a*k/(a+b)!=a*(k+1)/(a+b)) ans+=a*(k+1)/(a+b)*b;
  else ans+=b*(k+1)/(a+b)*a;
  
  cout<<ans<<endl;

  return 0;
}