NOI '11 P3 - Ali's Typewriter
View as PDFNational Olympiad in Informatics, China, 2011
Ali likes to collect
all kinds of strange gadgets. Most recently, he's gotten his hands on an
old-fashioned typewriter. The typewriter contains  keys, 
 of which
are the lowercase alphabet, and the other 
 are the uppercase letters
B and P.
Through further examination, Ali learned that the typewriter worked like this:
- Hitting a lowercase letter, the typewriter will append this letter
onto a special groove. There will be at least one such letter before
hitting 
P. - Hitting the 
Bkey, the typewriter will remove the last letter added to the groove. - Hitting the 
Pkey, the typewriter will take all the letters currently on the groove and print them onto the paper, switching lines afterwards. However, the letters on the groove will not disappear nor change. There will be at least one letter on the groove for this operation. 
For example, if Ali hits the keys aPaPBbP, then the following
will be printed onto the paper:
a
aa
ab
We number the strings printed onto the paper from  to 
. The
typewriter has a very interesting feature – there exists a hidden
numerical keypad where, if one were to input two numbers 
 (for 
)
the typewriter will display the number of times the
-th string appears in the 
-th string.
Ali is very excited after discovering this feature. He wants to write a program to perform the exact same feature. Can you help him?
Input Specification
The first line contains a single string, describing all of the keys that
Ali presses on the typewriter.
The second line contains a single integer , representing the number
of queries.
For the following  lines, each line will describe a query on the
hidden numerical keypad. The 
-th of these lines contains two
integers 
 and 
, indicating that the 
-th query is 
.
Output Specification
Output  lines, where the 
-th line contains a single integer – the
answer to the 
-th query.
Sample Input
aPaPBbP
3
1 2
1 3
2 3
Sample Output
2
1
0
Constraints
The attributes of all the test cases are outlined below.
| Test Case | Range of  | 
Range of  | 
Length of Strings | Keypresses (Line  | 
|---|---|---|---|---|
| / | ||||
| Individual lengths  Total length  | 
||||
| Total length  | ||||
| / | ||||
Problem translated to English by .
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