using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        while (true)
        {
            Array.Sort(c);
            if (c[2] - c[0] < 3) break;
            var mv = (c[2] - c[0]) / 3;
            c[2] -= mv * 2;
            c[0] += mv;
        }
        WriteLine(c.Min());
    }
}