#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

void initialize(char* s) {
    // This function is called once before all queries.
}

int answerQuery(int l, int r ,char* s) {
    int a[26] = {0};
    int sumo = 0 , sume = 0,sum = 0;
    for(int i = l-1 ; i < r ; i++ ){
        a[s[i]-97]++;
    }
    for(int i = 0 ; i < 26 ; i++){
       if((a[i]%2 == 0)&&(a[i] != 0))
           sumo++;
        else
            sume++;
    }
    sum = sumo+(sume/2);
    return sum;
    // Return the answer for this query modulo 1000000007.
}

int main() {
    char* s = (char *)malloc(512000 * sizeof(char));
    scanf("%s", s);
    initialize(s);
    int q; 
    scanf("%i", &q);
    for(int a0 = 0; a0 < q; a0++){
        int l; 
        int r; 
        scanf("%i %i", &l, &r);
        int result = answerQuery(l, r ,s);
        printf("%d\n", result);
    }
    return 0;
}