#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
inline void debugMode() {
#ifndef ONLINE_JUDGE
freopen("in.txt", "r", stdin);
freopen("out.txt", "w", stdout);
#endif // ONLINE_JUDGE
}
void solve() {
int n, q;
string s;
cin >> n >> s >> q;
vector<bool> used(n, 0);
while (q--) {
int l, r, d = 0, res = 0;
cin >> l >> r;
fill(used.begin(), used.end(), 0);
l--, r--;
for (int i = l; i <= r; i++) {
if (used[i])
continue;
if (s[i] == 'C')
d++;
else
d--;
if (d == -1) {
used[i] = 1;
res++;
d = 0;
}
}
d = 0;
for (int i = r; i >= l; i--) {
if (used[i])
continue;
if (s[i] == 'C')
d++;
else
d--;
if (d == -1) {
used[i] = 1;
res++;
d = 0;
}
}
cout << res << "\n";
}
}
signed main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
// debugMode();
int $ = 1;
// cin >> $;
while ($--) {
solve();
}
}
