#include <bits/stdc++.h>
using namespace std;
// cp-end
// cp-begin: segment-tree snippet
template <typename T, T (*Op)(T, T)> struct SegmentTree {
int N;
vector<T> t;
SegmentTree() {}
SegmentTree(int N) : N(N), t(2 * N) {};
void set(int p, T v) { t[p + N] = v; }
void build() {
for (int i = N - 1; i > 0; i--)
t[i] = Op(t[i << 1], t[i << 1 | 1]);
}
T query(int l, int r) {
r++;
T res[2];
bool set[2] = {false};
for (l += N, r += N; l < r; l >>= 1, r >>= 1) {
if (l & 1) res[0] = set[0] ? Op(res[0], t[l++]) : (set[0] = true, t[l++]);
if (r & 1) res[1] = set[1] ? Op(t[--r], res[1]) : (set[1] = true, t[--r]);
}
if (!set[0]) return res[1];
else if (!set[1]) return res[0];
else return Op(res[0], res[1]);
}
};
// cp-end
// cp-end
void solve();
int main() {
ios_base::sync_with_stdio(false); cin.tie(0);
cout << fixed << setprecision(12);
solve(); return 0;
}
struct Node {
int mnl, mnr, s;
static Node op(Node a, Node b) {
Node r;
r.mnl = min(a.mnl, a.s + b.mnl);
r.mnr = min(b.mnr, b.s + a.mnr);
r.s = a.s + b.s;
return r;
}
};
int N, Q;
string S;
SegmentTree<Node, Node::op> st;
void solve() {
cin >> N >> S >> Q;
st = SegmentTree<Node, Node::op>(N);
for (int i = 0; i < N; i++) {
if (S[i] == 'C') st.set(i, Node{0, 0, 1});
else st.set(i, Node{-1, -1, -1});
}
st.build();
while (Q--) {
int l, r; cin >> l >> r;
auto res = st.query(l - 1, r - 1);
cout << -min(res.mnl, res.mnr) << "\n";
}
}
