#include <bits/stdc++.h>
using namespace std;
int main() {
  long long a, b, c, sum, s1, s2, s3, mn;
  cin >> a >> b >> c;
  mn = min(a, min(c, b));
  sum = mn + (a - mn) / 3 + (b - mn) / 3 + (c - mn) / 3;
  long long p = mn - 1;
  if (p >= 0) {
    s1 = p + (a - p) / 3 + (b - p) / 3 + (c - p) / 3;
    sum = max(sum, s1);
  }
  p = mn - 2;
  if (p >= 0) {
    s2 = p + (a - p) / 3 + (b - p) / 3 + (c - p) / 3;
    sum = max(s2, sum);
  }
  p = mn - 3;
  if (p >= 0) {
    s2 = p + (a - p) / 3 + (b - p) / 3 + (c - p) / 3;
    sum = max(s2, sum);
  }
  cout << sum << endl;
  return 0;
}
