import java.util.Scanner;
import java.util.Arrays;
public class Yuki91{
	public static void main(String[] arg){
		Scanner sc = new Scanner(System.in);
		int[] a = new int[3];
		int temp,res=0;
		for(int i = 0;i<3;i++){
			a[i] = sc.nextInt();
		}
		Arrays.sort(a);
		res = a[0];
		for(int i = 0;i<3;i++){
			a[i] -= res;
		}
		while(a[1] > 0){
			if(a[2] < 3)break;
			res++;
			a[2] -=3;
			a[1]--;
			if(a[1] > a[2]){
				temp = a[1];
				a[1] = a[2];
				a[2] = temp;
			}
		}
		res += a[2] / 5;
		System.out.println(res);
	}
}