#define _USE_MATH_DEFINES

#include <iostream>		//cin, cout
#include <vector>		//vector
#include <algorithm>	//sort,min,max,count
#include <string>		//string,getline, to_string
#include <cstdlib>		//abs(int)
#include <utility>		//swap, pair
#include <deque>		//deque
#include <climits>		//INT_MAX
#include <bitset>		//bitset
#include <cmath>		//sqrt, ceil. M_PI, pow, sin
#include <ios>			//fixed
#include <iomanip>		//setprecision
#include <sstream>		//stringstream
#include <numeric>		//gcd, assumlate
#include <random>		//randam_device
#include <limits>		//numeric_limits

using namespace std;
constexpr long long int D_MOD = 1000000007;


int main() {

    int X, Y, Z;
    cin >> X >> Y >> Z;

    int ans = min(X, Y);
    int amari1 = max(X, Y) - ans;
    
    int temp = min(amari1, Z);
    ans += temp;
    amari1 -= temp;
    Z -= temp;

    if (Z != 0) {
        ans += Z / 2;
    }

    cout << ans << endl;

    return 0;

}