#include<iostream>
#include<cstdio>
#include<cstring>
#include <cstdlib>  
#include <cmath>   
#include<cctype>
#include<string>
#include<set>
#include <map>
#include<algorithm>
#include <functional>
#include<vector>
#include<climits>
#include<stack>
#include<queue>
#include <deque>
#include <climits>
#include <typeinfo>
#include <utility> 
#define all(x) (x).begin(),(x).end()
#define rep(i,m,n) for(int i = m;i < n;++i)
#define pb push_back
#define fore(i,a) for(auto &i:a)
#define rrep(i,m,n) for(int i = m;i >= n;--i)
#define INF INT_MAX/2
using namespace std;
using ll = long long;
using R = double;
const ll MOD = 1e9 + 7;
const ll inf = 1LL << 50;
struct edge { ll from; ll to; ll cost; };


int main(){
	vector<int>cnt(3);
	rep(i, 0, 3) {
		cin >> cnt[i];
	}
	sort(all(cnt));
	reverse(all(cnt));

	int ans;
	rrep(num,10000000,0) {
		if (num > cnt[0])continue;
		else if (cnt[0] >= num && num > cnt[1]) {
			int mustuse1 = (num - cnt[1]);
			int mustuse2 = (num - cnt[2]);
			int canuse = (cnt[0] - num) / 2;
			if (canuse >= mustuse1 + mustuse2) {
				ans = num;
				break;
			}
		}
		else if (cnt[1] >= num && num > cnt[2]) {
			int mustuse = (num - cnt[2]);
			int canuse1 = (cnt[1] - num)/2;
			int canuse2 = (cnt[0] - num)/2;
			if (canuse1 + canuse2 >= mustuse) {
				ans = num;
				break;
			}
		}
		else {
			ans = cnt[2];
			break;
		}
	}
	cout << ans << endl;
	return 0;
}