9 530792195 6
 0 0 10
 1944219055 454183506 1369298327
 914835 2742837 9234739
 10 10 0
 2 2 0
 0 0 1
 3 10 1007169359
 0 1 0
 1016450951 2 9
 0 2 10
 2147483648 0 2147483647
 92134834 23742837 92374738
 1 4 3
 382601556 881329640 791556039
 0 0 58
 5 10 6
 10 6 8
 6 8 10
 3 2 0
 1 4 4
 2147483630 2147483642 2147483610
 1 0 0
 18 67 5
 50606342 2 1134945035
 8 97 83
 2147483648 0 0
 92134834 23742837 92374737
 5 0 5
 772486757 1747374885 377299255
 1 0 1
 1 2 3
 0 3 2
 2147483648 2147483647 2147483648
 51 10 91
 9214834 2742837 9234739
 1 2 2147483648
 67 81 1
 92134834 23742837 92374739
 2 7 95
 3 0 2
 5 9 0
 1 10 2
 246543403 71853598 1504509195
 2147483648 2147483648 2147483648
 48 6 7
 2147483648 2147483648 0
 1358352906 27037371 1947040615

                                                       530792195
                                                                0
                                                       1944219055
                                                          2742837
                                                               10
                                                                2
                                                                0
                                                       1007169359
                                                                0
                                                       1016450951
                                                                2
 2147483648                                                         92374738
                                                                3
                                                        881329640
                                                                0
                                                               10
                                                                8
                                                                8
                                                                2
                                                                4
                                                       2147483630
                                                                0
                                                               67
                                                         50606342
                                                               97
                                                                0
                                                         92374737
                                                                5
                                                        772486757
                                                                1
                                                                3
                                                                2
 2147483648                                                               91
                                                          9234739
 2147483648                                                               67
                                                         92374739
                                                               95
                                                                2
                                                                9
                                                               10
                                                       1504509195
 2147483648                                                               48
 2147483648                                                       1947040615

import java.util.*;

    public class Test_Project_0001 
    {
        public static void main(String[] args)
        {
            Scanner sc = new Scanner(System.in);
            
            int R = sc.nextInt();
            int G = sc.nextInt();
            int B = sc.nextInt();
            int count = 0;
            
            while((R!=0 && G!=0)||(R!=0 && B!=0)||(G!=0 && B!=0))
            {
                
                if(R == G)
                {
                    B += R;
                    count += R;
                    R = G = 0;
                }
                else if(G == B)
                {
                    R += G;
                    count += G;
                    G = B = 0;
                }
                else if(B == R)
                {
                    G += B;
                    count += B;
                    R = B = 0;
                }
                if(R < G && R < B)
                {
                    if(G > B && (B-R)%2 == 0) 
                    {
                        count += B;
                        R = B = 0;
                    }
                    else if (B > G && (G-R)%2 == 0) 
                    {
                        count += G;
                        R = B = 0;
                    }
                    else if(G > B && (G-R)%2 == 0 && (G-R)/2 < B) 
                    {
                        count += G;
                        R = B = 0;
                    }
                    else if (B > G && (B-R)%2 == 0 && (B-R)/2 < G) 
                    {
                        count += B;
                        R = B = 0;
                    }
                    else
                    {
                        count++;
                        R++;
                        G--;
                        B--;
                    }
                }
                if(G < R && G < B)
                {
                    if(R > B && (B-G)%2 == 0) 
                    {
                        count += B;
                        R = B = 0;
                    }
                    else if(B > R && (R-G)%2 == 0) 
                    {
                        count += R;
                        R = B = 0;
                    }
                    else if(R < B && (B-G)%2 == 0 && (B-G)/2 < B) 
                    {
                        count += B;
                        R = B = 0;
                    }
                    else if(B < R && (R-G)%2 == 0 && (R-G)%2 < R) 
                    {
                        count += R;
                        R = B = 0;
                    }
                    else
                    {
                        G++;
                        R--;
                        B--;
                    }
                }
                if(B < G && B < R)
                {
                    if(G > R && (R-B)%2 == 0) 
                    {
                        count += R;
                        R = B = 0;
                    }
                    else if(R > G && (G-B)%2 == 0) 
                    {
                        count += G;
                        R = B = 0;   
                    }
                    else if(G < R && (R-B)%2 == 0 && (R-B)/2 < R) 
                    {
                        count += R;
                        R = B = 0;
                    }
                    else if(R < G && (G-B)%2 == 0 && (G-B)/2 < G) 
                    {
                        count += G;
                        R = B = 0;   
                    }
                    else
                    {
                        count++;
                        R--;
                        G--;
                        B++;
                    }
                }
            }
            
            System.out.print(count);
        }
    }