#ifndef _GLIBCXX_NO_ASSERT
#include <cassert>
#endif
#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>

//#ifdef __GXX_EXPERIMENTAL_CXX0X__
#include <ccomplex>
#include <cfenv>
#include <cinttypes>
#include <cstdbool>
#include <cstdint>
#include <ctgmath>
#include <cwchar>
#include <cwctype>
//#endif

#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>

#include <array>
//#include <atomic>
#include <chrono>
//#include <condition_variable>
#include <forward_list>
//#include <future>
#include <initializer_list>
//#include <mutex>
#include <random>
#include <ratio>
#include <regex>
#include <system_error>
//#include <thread>
#include <tuple>
#include <typeindex>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>


using namespace std;

int main ()
{
	array<int,3> A;
	for( size_t i = 0; i < 3; i++ )
	{
		cin >> A[i];
	}
	sort ( A.begin () , A.end () );
	int ans = A[0];
	A[1] -= A[0];
	A[2] -= A[0];
	while( A[1] + A[2] > 3 &&max(A[1],A[2])>2)
	{
		if( A[1] > A[2] )
		{
			A[1]-=3;
			A[2]--;
			ans++;
		} else
		{
			A[2] -= 3;
			A[1]--;
			ans++;
		}
	}
	cout << ans << endl;
}