#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <algorithm>
#include <cmath>
#include <sstream>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
#define all(c) (c).begin(), (c).end()
#define loop(i,a,b) for(ll i=a; i<ll(b); i++)
#define rep(i,b) loop(i,0,b)
#ifdef DEBUG
#define dump(...) (cerr<<#__VA_ARGS__<<" = "<<(DUMP(),__VA_ARGS__).str()<<" ["<<__LINE__<<"]"<<endl)
struct DUMP:ostringstream{template<class T>DUMP &operator,(const T&t){if(this->tellp())*this<<", ";*this<<t;return *this;}};
#else
#define dump(...)
#endif
// 1 1 1
// 1 3
// 5

int main(){
    int a[3];
    while(cin>>a[0]){
        rep(i,2)cin>>a[i+1];
        int m=max({a[0],a[1],a[2]});
        int ans=0;
        rep(i,m){
            if(a[2]<2) break;
            sort(a,a+3);
            a[0]++;
            a[2]-= 2;
            dump(a[0],a[1],a[2]);
            ans=max(ans,min({a[0],a[1],a[2]}));
        }
        cout << ans << endl;
    }
}