#include <iostream>
#include <queue>
#include <vector>
#include <algorithm>
using namespace std;

int r,g,b;




int main()
{
	cin >> r >> g >> b;

	vector<int> vec;

	vec.push_back(r);
	vec.push_back(g);
	vec.push_back(b);

	sort(vec.begin(),vec.end());

	int cou1 = vec[0];

	for(int& v : vec)
	{
		v -= cou1;
	}
	int cou2 = 0;

	int a = vec[1];
	int b = vec[2];
	// a < b;
	while(true)
	{
		if(a >= 1 && b >= 3)
		{
			cou2++;
			a -= 1;
			b -= 3;
			if(a > b) swap(a,b);
		}
		else
		{
			break;
		}
	}
	cout << cou1 + cou2 << endl;
	return 0;
}