#include <iostream>
#include <cstring>
#include <cmath>
using namespace std;

int main()
{

char line1[10000];
char line2[10000];
while(cin >> line1 >> line2)
{
cout << abs(int(line1[0]-'A')-int(line2[0]-'A'))<< endl;
}

return 0;
}