#include <bits/stdc++.h>
#define all(vec) vec.begin(), vec.end()
using namespace std;
using ll = long long;
using P = pair<int, int>;
constexpr ll INF = (1LL << 30) - 1LL;
constexpr ll LINF = (1LL << 60) - 1LL;
constexpr ll MOD = 1e9 + 7;
template <typename T> void chmin(T &a, T b) { a = min(a, b); }
template <typename T> void chmax(T &a, T b) { a = max(a, b); }
int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int x, y, z;
    cin >> x >> y >> z;
    int res = 0;
    int t = min(x, y);
    res += t;
    x -= t;
    y -= t;
    res += min(max(x, y), z);
    z -= min(max(x, y), z);
    res += z / 2;
    cout << res << endl;
}