#include <iostream>
#include <algorithm>
using namespace std;
int main(){
	int r,g,b;	cin>>r>>g>>b;
	int mi=r;
	if(mi>g)	mi=g;
	if(mi>b)	mi=b;
	int cnt=mi;	r-=mi;	g-=mi;	b-=mi;
	while(r+g+b>=3){
		if(r+g+b==4&&(r==g||g==b||b==r))	break;
		if(r==0){
			if(g>b){
				mi=min(g/3,b);
				cnt+=mi;	g-=mi*3;	b-=mi;
			}
			else{
				mi=min(g,b/3);
				cnt+=mi;	g-=mi;	b-=mi*3;
			}
		}
		else if(g==0){
			if(r>b){
				mi=min(r/3,b);
				cnt+=mi;	r-=mi*3;	b-=mi;
			}
			else{
				mi=min(r,b/3);
				cnt+=mi;	r-=mi;	b-=mi*3;
			}
		}
		else{
			if(r>g){
				mi=min(r/3,g);
				cnt+=mi;	r-=mi*3;	g-=mi;
			}
			else{
				mi=min(r,g/3);
				cnt+=mi;	r-=mi;	g-=mi*3;
			}
		}
	}
	cnt+=(r/5)+(g/5)+(b/5);
	cout<<cnt<<endl;
	return 0;
}