#!/bin/python3

import sys
import math
#def initialize(s):
    # This function is called once before all queries.

def answerQuery(l, r, s):
    # Return the answer for this query modulo 1000000007.
    ss = s[l-1:r]
    
    su = set(ss)
    
    o = -1
    c = 0
    for a in list(su):
        acount = ss.count(a)
        
        if acount == 1 and o < 0:
            o += 1
            continue
        c += math.ceil(acount/2)
        
    return c
    
    
if __name__ == "__main__":
    s = input().strip()
#    initialize(s)
    q = int(input().strip())
    for a0 in range(q):
        l, r = input().strip().split(' ')
        l, r = [int(l), int(r)]
        result = answerQuery(l, r, s)
        print(result)