#include <bits/stdc++.h>
using namespace std;
int toInt(string s) {
  int r = 0;
  istringstream sin(s);
  sin >> r;
  return r;
}
long long toInt64(string s) {
  long long r = 0;
  istringstream sin(s);
  sin >> r;
  return r;
}
double toDouble(string s) {
  double r = 0;
  istringstream sin(s);
  sin >> r;
  return r;
}
string toString(long long n) {
  string s, s1;
  while (n / 10 > 0) {
    s += (char)((n % 10) + 48);
    n /= 10;
  }
  s += (char)((n % 10) + 48);
  n /= 10;
  s1 = s;
  for (long long i = 0; i < s.length(); i++) s1[(s.length() - 1) - i] = s[i];
  return s1;
}
bool isUpperCase(char c) { return c >= 'A' && c <= 'Z'; }
bool isLowerCase(char c) { return c >= 'a' && c <= 'z'; }
bool isLetter(char c) { return c >= 'A' && c <= 'Z' || c >= 'a' && c <= 'z'; }
bool isDigit(char c) { return c >= '0' && c <= '9'; }
char toLowerCase(char c) { return (isUpperCase(c)) ? (c + 32) : c; }
char toUpperCase(char c) { return (isLowerCase(c)) ? (c - 32) : c; }
int main() {
  long long f[3];
  cin >> f[0] >> f[1] >> f[2];
  sort(f, f + 3);
  long long count1 = 0;
  count1 += f[0];
  int a = count1;
  f[1] -= count1;
  f[2] -= count1;
  count1 += f[1] / 3;
  count1 += f[2] / 3;
  f[1] += f[0];
  f[2] += f[0];
  long long count2 = (f[0] / 3) + (f[1] / 3) + (f[2] / 3);
  long long p = max((f[1] - f[0]) % 3, (f[2] - f[0]) % 3);
  long long pp = -1;
  for (long long i = 0; i < p + 1; i++)
    pp = max(i / 3 + (f[1] - f[0] + i) / 3 + (f[2] - f[0] + i) / 3 + f[0] - i,
             pp);
  long long count3 = 0;
  count3 = (f[0] / 3) + (f[1] / 3) + (f[2] / 3);
  f[0] %= 3;
  f[1] %= 3;
  f[2] %= 3;
  sort(f, f + 3);
  count3 += f[0];
  cout << max(count1, max(count2, max(count3, pp))) << endl;
}
