K-th Occurrence of a Character

You are given a string \(S\) consisting of lowercase English letters and \(Q\) queries. Each query specifies a character \(c\) and an integer \(k\). For every query, you must determine the position (1-indexed) of the \(k\)-th occurrence of the character \(c\) in \(S\). If \(c\) occurs fewer than \(k\) times, output \(-1\).

Input Format: The first line contains the string \(S\). The second line contains an integer \(Q\) representing the number of queries. Each of the following \(Q\) lines contains a character and an integer separated by spaces.

Output Format: For each query, output the answer on a new line.

inputFormat

The input is read from standard input (stdin) and has the following format:

S
Q
c1 k1
c2 k2
...
cQ kQ

where:

• S is a non-empty string of lowercase English letters.
• Q is the number of queries.
• Each query consists of a character c and an integer k.

outputFormat

For each query, output a single integer on a new line. The integer is the 1-indexed position of the \(k\)-th occurrence of the given character \(c\) in \(S\) or \(-1\) if it does not exist.

## sample

ababab
3
a 1
b 2
c 1

1
4
-1

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