#include <bits/stdc++.h>
using namespace std;
bool com(pair<int, int> x, pair<int, int> y) {
  if (x.first == y.first) return x.second < y.second;
  return x.first < y.first;
}
long long int power(long long int x, long long int y) {
  long long int prod = 1;
  while (y) {
    if (y & 1) prod = (prod * x) % 1000000007;
    x = (x * x) % 1000000007;
    y /= 2;
  }
  return prod;
}
const int N = 1e5 + 9;
void solve() {
  long long int a[3];
  cin >> a[0] >> a[1] >> a[2];
  sort(a, a + 3);
  long long int ans = 0;
  for (long long int i = a[0]; i >= max(0ll, a[0] - 3ll); i--) {
    ans = max(ans, i + (a[1] - i) / 3ll + (a[2] - i) / 3ll);
  }
  cout << ans;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int t = 1;
  while (t--) solve();
  return 0;
}
