#include <bits/stdc++.h>
using namespace std;
int a, b, c;
int pnt(int t) { return t + (a - t) / 3 + (b - t) / 3 + (c - t) / 3; }
int main() {
  cin >> a >> b >> c;
  int t = min(min(a, b), c);
  cout << max(max(pnt(t), pnt(max(t - 1, 0))), pnt(max(t - 2, 0)));
}
