#include <bits/stdc++.h>
using namespace std;
int main()
{
string n, m1, m2;
cin >> n;
copy_if(begin(n), end(n), back_inserter(m1), [] (char c) { return ((c - '0') % 2) ? true : false; });
copy_if(begin(n), end(n), back_inserter(m2), [] (char c) { return ((c - '0') % 2) ? false : true; });
cout << abs(stoi(m1) - stoi(m2)) << '\n';
return 0;
}