#!/bin/python3

import sys

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

def answerQuery(l, r,s):
    k=s[l-1:r+1]
    m=dict()
    f=0
    j=0
    for i in k:
        if i not in m:
            m[i]=1
        else:
            m[i]+=1
    for i in m.values():
        if i%2 !=0:
            j+=1
        else:
            i=i//2
            f+=i
    if j!=0:
        return f+j-1
    else:
        return f
    # Return the answer for this query modulo 1000000007.

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)