#include <bits/stdc++.h>

using namespace std;
int f[200];
void initialize(int f[]) {
    for(int i=97;i<123;i++)
        f[i]=0;
    // This function is called once before all queries.
}

int answer(int l, int r,string s) {
    initialize(f);
    for(int i=l;i<r;i++)
    {
         f[s[i]]++;
       
     }
    int sum=0,c=0;
    for(int i=97;i<123;i++) 
    {
      sum=sum+f[i]/2;
        c=c+f[i]%2;
    }
  return sum+c;
    // Return the answer for this query modulo 1000000007.
}

int main() {
    string s;
    cin >> s;
  
    int q;
    cin >> q;
    for(int a0 = 0; a0 < q; a0++){
        int l;
        int r;
        cin >> l >> r;
        int result = answer(l, r,s);
        cout << result << endl;
    }
    return 0;
}