#include <bits/stdc++.h>
long long gcd(long long a, long long b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
long long lcm(long long a, long long b) { return (a * b) / gcd(a, b); }
const int MOD = 1e12 + 7;
const int MAX = 1e6 + 2;
const int INF = 0x3f3f3f3f;
bool IsPrime(long long x) {
  if (x < 2) {
    return false;
  }
  for (long long p = 2; p * p <= x; ++p)
    if (x % p == 0) return false;
  return true;
}
using namespace std;
int main() {
  long long r, g, b, cnt = 0;
  cin >> r >> g >> b;
  for (long long i = 0; i < 3; i++) {
    if (i > r || i > b || i > g) break;
    cnt = max(cnt, i + (r - i) / 3 + (g - i) / 3 + (b - i) / 3);
  }
  cout << cnt << endl;
  return 0;
}
