#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<ll> VL;
typedef vector<VL> VVL;
typedef pair<int, int> PII;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()
#define MOD 1000000007
#define INF (1LL<<25)     //33554432
#define PI 3.14159265359
#define EPS 1e-12
//#define int ll

signed main(void)
{
  int r, g, b;
  cin >> r >> g >> b;
  const int n = r+g+b;

  int ret = 0;
  REP(i, n) {
    if(r > 0 && g > 0 && b > 0) {
      int tmp = min(r, g);
      tmp = min(tmp, b);
      r -= tmp; g -= tmp;  b -= tmp;
      ret += tmp;
    }
    if((r == 0 && g == 0) || (g == 0 && b == 0) || (b == 0 && g == 0)) {
      int tmp = max(r, g);
      tmp = max(tmp, b);
      ret += tmp/5;
      break;
    }
    if(r+g+b <= 3) break;
    if(r == 0) {
      if(g <= b) {b -= 2; r++;}
      else {g -= 2; r++;}
    }
    if(g == 0) {
      if(r <= b) {b -= 2; g++;}
      else {r -= 2; g++;}
    }
    if(b == 0) {
      if(g <= r) {r -= 2; b++;}
      else {g -= 2; b++;}
    }
  }

  cout << ret << endl;

  return 0;
}