#include <iostream>
#include <functional>
#include <vector>
#include <cmath>

using ll = long long int;

ll BinarySearch(ll low, ll high, std::function<bool(ll)> calc){
    if(high-low==1){
        return low;
    }
    if(calc((high+low)/2)){
        return BinarySearch((high+low)/2, high, calc);
    }else{
        return BinarySearch(low, (high+low)/2, calc);
    }
}

int main(){
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    
    ll R, G, B;
    std::cin >> R >> G >> B;
    
    auto calc = [=](ll n) -> bool {
        std::vector<ll> stone({R-n, G-n, B-n});
        ll changeableNum = 0;
        for(auto i : stone){
            changeableNum += (i>0) ? i/2 : i;
        }
        return changeableNum>=0;
    };
    std::cout << BinarySearch(0, std::pow(2, 24), calc) << "\n";
    
    return 0;
}