B. Black and White
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Nancy is learning about pianos and music theory!

Her piano looks like the above, and it consists of various black and white keys. The white keys are indexed by number-letter pairs, starting at C1 and ending at C8. The indexing system begins C1, D1, E1, F1, G1, A1, B1, C2, D2, and so on until A7, B7, C8. Nancy wonders, between a particular pair of white keys, how many black keys are there? Can you help her out with various queries?

Input

The input will consist of a single line containing a pair of white key indices (each represented by a letter between A and G and a number between 1 and 8), separated by a space. It is guaranteed that the first white key index is smaller than or equal to the second one, based on the indexing scheme mentioned above. It is also guaranteed that both of the indices appear between the range of C1 and C8.

Output

The output should consist of a single line containing a single integer, the number of black keys that appear on Nancy's piano between the two white keys specified in the input.

Examples
Input
C1 C8
Output
35
Input
A5 D6
Output
2
Note

In the first sample test case, the range of keys is the entire piano, so all of the black keys are counted, for a total of 35.