#define _USE_MATH_DEFINES
#include  <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <string>
#include<math.h>
#include<iomanip>
#include<stdio.h>
#include <stdlib.h>
#include<stdio.h>
#include <queue>
#include<map>
#include <fstream>
#include <sstream>
#include<set>
#include<stack>
#include<time.h>
#include <sys/types.h>
#include <tuple>
#include <numeric>
#include <iterator>

typedef long long int ll;
//#include<bits/stdc++.h>


using namespace std;

ll gcd(ll a, ll b) {
    if (a < b)swap(a, b);
    if (b == 0)return a;
    return gcd(b, a % b);
}
int lcm(int a, int b) {
    return a * b / gcd(a, b);
}







int main()
{

    int Q;
    Q = 1;
    //cin >> Q;   

    while (Q--) {
        vector<ll>a(3);
        cin >> a[0] >> a[1] >> a[2];
        sort(a.rbegin(), a.rend());
        ll ans = 0;
        ans += a[2];
        a[0] -= a[2]; a[1] -= a[2]; a[2] = 0;
        while (a[1]>0&&a[0]>2) {
            
            ans ++;
            a[0] -=3; a[1] -= 1;
            if (a[0] < a[1])swap(a[0], a[1]);
        }
        //cout << ans << endl;
        ans += a[0] / 5;
        cout << ans;


    }
    return 0;
}