import java.util.Arrays;
import java.util.Scanner;

public class Main {

	@SuppressWarnings("resource")
	public static void main(String args[]) {
		Scanner scanner = new Scanner(System.in);
		int r=scanner.nextInt();
		int b=scanner.nextInt();
		int g=scanner.nextInt();
		int x[]=new int[3];
		x[0]=r;
		x[1]=b;
		x[2]=g;
		Arrays.sort(x);
		int tmp=(x[2]-x[0])/3;
		x[0]+=tmp;
		x[2]-=tmp*2;
		Arrays.sort(x);
		tmp=(x[2]-x[0])/3;
		x[0]+=tmp;
		x[2]-=tmp*2;
		Arrays.sort(x);
		System.out.println(x[0]);
	}
}