#include <bits/stdc++.h>
using namespace std;
void _print(long long int t) { cerr << t; }
void _print(int t) { cerr << t; }
void _print(string t) { cerr << t; }
void _print(char t) { cerr << t; }
void _print(long double t) { cerr << t; }
void _print(double t) { cerr << t; }
void _print(unsigned long long t) { cerr << t; }
template <class T, class V>
void _print(pair<T, V> p);
template <class T>
void _print(vector<T> v);
template <class T>
void _print(set<T> v);
template <class T, class V>
void _print(map<T, V> v);
template <class T>
void _print(multiset<T> v);
template <class T, class V>
void _print(pair<T, V> p) {
  cerr << "{";
  _print(p.first);
  cerr << ",";
  _print(p.second);
  cerr << "}";
}
template <class T>
void _print(vector<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(set<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(multiset<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T, class V>
void _print(map<T, V> v) {
  cerr << "[ ";
  for (auto i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
long long binpow(long long a, long long b, long long m);
int binarySearch(vector<int>& v, int l, int r, int x);
void solve() {
  long long int r, g, b;
  cin >> r >> g >> b;
  long long int ans = r / 3 + g / 3 + b / 3;
  int e1 = r % 3;
  int e2 = g % 3;
  int e3 = b % 3;
  int e = min(e1, min(e2, e3));
  e1 -= e;
  e2 -= e;
  e3 -= e;
  if (e1 + e2 + e3 == 4 && r > 0 && b > 0 && g > 0) ans++;
  ans += e;
  cout << ans;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  clock_t start, end;
  start = clock();
  { solve(); }
  end = clock();
  double time_taken = double(end - start) / double(CLOCKS_PER_SEC);
  return 0;
}
long long binpow(long long a, long long b, long long m) {
  a %= m;
  long long res = 1;
  while (b > 0) {
    if (b & 1) res = res * a % m;
    a = a * a % m;
    b >>= 1;
  }
  return res;
}
int binarySearch(vector<int>& v, int l, int r, int x) {
  while (l <= r) {
    int m = l + (r - l) / 2;
    if (v[m] == x) return m;
    if (v[m] < x)
      l = m + 1;
    else
      r = m - 1;
  }
  return -1;
}
