#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main(){
  vector<int> ar(3);
  for(int i = 0; 3 > i; i++){
    cin>>ar[i];
  }
  sort(ar.begin(),ar.end());
  int ans = ar[0];
  for(int i = 0; 3 > i; i++){
    ar[i] -= ans;
  }
	int prevans = ans;
  while(true){
		if(ar[1]){
			if(ar[2]-ar[1]>=2){
				int z = (ar[2]-ar[1])/2;
				ar[0] = z;
				ar[2]-=ar[0]*2;
				int mn = min({ar[0],ar[1],ar[2]});
				ans += mn;
				for(int i = 0; 3 > i; i++){
					ar[i]-=mn;
				}
			}else{
				if(ar[2]>2){
					ans++;
					ar[2]-=2;
					ar[1]-=1;
					if(ar[1]>ar[2])swap(ar[1],ar[2]);
				}else{
					break;
				}
			}
		}else{
			ans += ar[2]/5;
			break;
		}
		if(ans==prevans)break;
	}
	cout << ans << endl;
}