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

public class Main {

	public static void main (String[] args) {

		Scanner sc = new Scanner(System.in);

		int r = sc.nextInt();
		int g = sc.nextInt();
		int b = sc.nextInt();

		System.out.println(solve(new int[]{r, g, b}));

		sc.close();

	}

	public static int solve (int[] nums) {

		//System.out.println(Arrays.toString(nums));

		Arrays.sort(nums);

		int ret = nums[0];
		nums[1] -= nums[0];
		nums[2] -= nums[0];

		if (nums[2] == 0)
			return ret;
		else if (nums[1] == 0)
			return ret + nums[2] / 5;
		else if (nums[2] - nums[1] >= 2) {
			int sub = nums[2] - nums[1];
			ret += sub / 2;
			nums[2] -= sub;
			return ret + solve(nums);
		} else if (nums[2] - nums[1] == 1)
			return nums[2] % 2 == 1 ? (nums[2] - 1) / 2 : (nums[1] - 1) / 2;
		else
			return nums[2] % 4 == 3 ? nums[2] / 4 + 1 : nums[2] / 4;
	}

}