#include<iostream>
#include<iomanip>
#include<string>
#include<algorithm>
#include<vector>
#include<set>
#include<list>
#include<queue>
#include<math.h>
#include<bitset>
using ll = long long;
using namespace std;

int main(){
    int r, g, b;
    ll ans = 0;
    cin >> r >> g >> b;
    vector<int> l = {r, g, b};
    do {
        int t;
        sort(l.begin(), l.end());
        t = l[0];
        ans += t;
        l[0] -= t;
        l[1] -= t;
        l[2] -= t;
        t = 0;
        if (l[2] > 5 && l[1] < 5){
            t = (l[2] - l[1])/5;
            l[0] += t;
            l[1] += t;
            l[2] -= t*4;
        } else if (l[2] > 5){
            t = (l[2] - l[1])/2;
            l[0] += t;
            l[2] -= t*2;
        } else if (l[1] >= 3){
            t = 1;
            l[0]++;
            l[1] -= 2;
        }
    } while ((l[0] != 0 && l[1] != 0 && l[2] != 0) || l[2] >= 3);
    cout << ans << endl;
}