using System;
public class Program
{
public static void Main()
string t = Console.ReadLine();
byte[] t_bytes = new byte[t.Length];
int output = 0;
for(int i = 0; i < t.Length; i++)
t_bytes[i] = (byte)t[i];
}
foreach(byte v in t_bytes)
if(v % 2 != 0)
output += v;
Console.WriteLine(output);