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) {

		Arrays.sort(nums);

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

		if (nums[0] != 0) {
			nums[1] -= nums[0];
			nums[2] -= nums[0];
			//System.out.println(nums[0]);
			return nums[0] + solve(new int[]{0, nums[1], nums[2]});
		}

		if (nums[2] == 0) return 0;

		if (nums[1] == 0) return nums[2] / 5;

		if (nums[2] - nums[1] >= 2) {
			int sub = nums[2] - nums[1];
			int sub_half = sub / 2;
			if (sub_half <= nums[1]) {
				nums[2] -= sub + sub_half;
				nums[1] -= sub_half;
				//System.out.println(sub_half);
				return sub_half + solve(nums);
			} else {
				//System.out.println(nums[1]);
				return nums[1] + solve(new int[]{0, 0, nums[2] - nums[1]});
			}
		} 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 == 0 ? nums[2] / 2 : (nums[2] - 1) / 2;
	}

}