#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
using ll = long long;

int main(){
    vector<int> a(3);
    cin >> a[0] >> a[1] >> a[2];
    int t = 100000000;
    while(t--){
        sort(a.begin() , a.end());
        if(a[2] >= 2 && a[2] > a[0]){
            a[0] += 1;
            a[2] -= 2;
        }
        //cout << a[0] << " : " << a[1] << " : " << a[2] << endl;
    }
    cout << min({a[0] , a[1] , a[2]}) << endl;
    return 0;
}