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

public class No91 {

	public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		int[] rgb = new int[3];
		for(int i = 0;i < 3;i++) {
			rgb[i] = scanner.nextInt();
		}
		scanner.close();
		
		Arrays.sort(rgb);
		
		int count = 0 , min = 0;
		count += rgb[0];
		min= rgb[0];
		for(int i = 0;i < 3;i++) {
			rgb[i] -= min;
			if(rgb[i] / 4 > 0) {
				count += rgb[i] / 4;
				rgb[i] %= 4;
			}
		}
		
		if(rgb[1] + rgb[2] >= 4 && (rgb[1] != 2 || rgb[2] != 2)) {
			count += 1;
		}
		
		System.out.println(count);
		
	}

}