#include <bits/stdc++.h>

using namespace std;

const int MAX = 5e5 + 5;

int n, q;
int s[MAX];
int a[MAX];
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    
    cin >> n >> q;
    
    for (int i = 1; i <= n; i++) 
    {
        char x; cin >> x;
        a[i] = x - 'A';
        if (i > 1) s[i] = s[i-1] + (a[i] == a[i-1]);
    }
    
    while(q--)
    {
        int l, r; cin >> l >> r;
        cout << s[r] - s[l] << "\n";
    }
    
    return 0;
}