#include <bits/stdc++.h>
using namespace std;
int main() {
  int r, g, b;
  cin >> r >> g >> b;
  int res0 = (r / 3) + (g / 3) + (b / 3) + min(min(r % 3, g % 3), b % 3);
  int mixed1 = min(min(1, r), min(g, b));
  int R = r - mixed1;
  int G = g - mixed1;
  int B = b - mixed1;
  int res1 =
      mixed1 + (R / 3) + (G / 3) + (B / 3) + min(min(R % 3, G % 3), B % 3);
  int mixed2 = min(min(2, r), min(g, b));
  R = r - mixed2;
  G = g - mixed2;
  B = b - mixed2;
  int res2 =
      mixed2 + (R / 3) + (G / 3) + (B / 3) + min(min(R % 3, G % 3), B % 3);
  cout << max(res0, max(res1, res2)) << endl;
  return 0;
}
