#include <bits/stdc++.h>
using namespace std;
string a;
string ans;
int main()
{
    bool plus;
    int suma = 0, sumb = 0;
    cin >> a;
    if (a.size() % 8)
    {
        cout << "Error" << endl;
        return 0;
    }
    else
    {
        plus = false;
        for (int i = 1; i * 8 <= a.size(); i++)
        {
            for (int j = 1; j <= 8; j++)
            {
                if (a[i * 8 - j] != '0' && a[i * 8 - j] != '1')
                {
                    cout << "Error" << endl;
                    return 0;
                }
            }
            if (plus)
            {
                if (a[i * 8 - 8] == '0')
                {
                    for (int j = 8; j >= 1; j--)
                    {
                        if (a[i * 8 - j] - '0' == 1)
                        {
                            sumb += 1 << (j - 1);
                        }
                    }
                    ans += to_string(suma / 2 + sumb / 2);
                    suma = 0, sumb = 0;
                    plus = false;
                    continue;
                }
                else
                {
                    cout<<"Error"<<endl;
                    return 0;
                }
            }
            if (a[i * 8 - 8] == '1' && a[i * 8 - 7] == '0' && a[i * 8 - 6] == '1')
            {
                int num = 0;
                for (int j = 5; j >= 1; j--)
                {
                    if (a[i * 8 - j] - '0' == 1)
                    {
                        num += 1 << (j - 1);
                    }
                }
                ans += 'A' + num;
            }
            else
            {
                if (a[i * 8 - 8] == '1' && a[i * 8 - 7] == '1' && a[i * 8 - 6] == '1')
                {
                    ans += ' ';
                }
                else
                {
                    if (a[i * 8 - 8] == '0')
                    {
                        for (int j = 8; j >= 1; j--)
                        {
                            if (a[i * 8 - j] - '0' == 1)
                            {
                                suma += 1 << (j - 1);
                            }
                        }
                        plus = true;
                    }
                    else
                    {
                        cout << "Error" << endl;
                        return 0;
                    }
                }
            }
        }
    }
    if (plus)
    {
        cout << "Error" << endl;
        return 0;
    }
    cout << ans;
    return 0;
}