#include <bits/stdc++.h>
using namespace std;
const int N = 500005;
struct node {
int l, r, ans, sum;
} aint[4 * N + 5];
node join(node a, node b) {
node c;
c.l = max(a.l, a.sum + b.l);
c.r = max(b.r, b.sum + a.r);
c.sum = a.sum + b.sum;
c.ans = max({a.ans + b.sum, a.sum + b.ans, a.l + b.r});
return c;
}
void build(int pos, int st, int dr, string &s) {
if (st == dr) {
if (s[st - 1] == 'C')
aint[pos] = {0, 0, 0, -1};
else
aint[pos] = {1, 1, 1, 1};
return;
}
int mid = (st + dr) >> 1;
build (2 * pos, st, mid, s);
build (2 * pos + 1, mid + 1, dr, s);
aint[pos] = join(aint[2 * pos], aint[2 * pos + 1]);
}
node query(int pos, int st, int dr, int l, int r) {
if (l <= st && dr <= r)
return aint[pos];
int mid = (st + dr) >> 1;
if (r <= mid)
return query(2 * pos, st, mid, l, r);
else if (mid < l)
return query(2 * pos + 1, mid + 1, dr, l, r);
return join(query(2 * pos, st, mid, l, r), query(2 * pos + 1, mid + 1, dr, l, r));
}
signed main() {
int n;
cin >> n;
string s;
cin >> s;
build(1, 1, n, s);
int q;
cin >> q;
vector<int> last(n, q + 1);
while (q --) {
int l, r;
cin >> l >> r;
cout << query(1, 1, n, l, r).ans << '\n';
}
}
