#include <bits/stdc++.h>
using namespace std;
void boost() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
}
template <typename T>
void take(vector<T>& v) {
  for (T& val : v) cin >> val;
}
template <typename T>
void show(vector<T>& v, string end = " ", string after = "\n") {
  for (T& val : v) cout << val << end;
  cout << after;
}
void solve() {}
int main() {
  boost();
  int r, g, b;
  cin >> r >> g >> b;
  if (r == 0 || g == 0 || b == 0) {
    cout << (r / 3 + g / 3 + b / 3) << endl;
    return (0);
  }
  int ans = min(r, min(g, b));
  r -= ans;
  g -= ans;
  b -= ans;
  ans += r / 3 + g / 3 + b / 3;
  r %= 3;
  g %= 3;
  b %= 3;
  if (r == 0 && g == 2 && b == 2) ans++;
  if (g == 0 && r == 2 && b == 2) ans++;
  if (b == 0 && r == 2 && g == 2) ans++;
  cout << ans << endl;
  return (0);
}
