#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int N;
if (!(cin >> N)) return 0;
string s; cin >> s;
s = " " + s; // 1-index
// Prefix sums P[0..N]
vector<int> P(N+1, 0);
for (int i = 1; i <= N; ++i) {
P[i] = P[i-1] + (s[i] == 'C' ? 1 : -1);
}
// Build logs for sparse table
int M = N + 1; // P has indices [0..N]
vector<int> lg(M+1, 0);
for (int i = 2; i <= M; ++i) lg[i] = lg[i/2] + 1;
int K = lg[M];
// Sparse tables for min and max over P
vector<vector<int>> stMin(K+1, vector<int>(M));
vector<vector<int>> stMax(K+1, vector<int>(M));
for (int i = 0; i < M; ++i) stMin[0][i] = stMax[0][i] = P[i];
for (int k = 1; k <= K; ++k) {
int len = 1 << k;
int half = len >> 1;
for (int i = 0; i + len - 1 < M; ++i) {
stMin[k][i] = min(stMin[k-1][i], stMin[k-1][i+half]);
stMax[k][i] = max(stMax[k-1][i], stMax[k-1][i+half]);
}
}
auto rmqMin = [&](int L, int R) {
// query min over P[L..R], with 0 <= L <= R <= N
int len = R - L + 1;
int k = lg[len];
return min(stMin[k][L], stMin[k][R - (1<<k) + 1]);
};
auto rmqMax = [&](int L, int R) {
int len = R - L + 1;
int k = lg[len];
return max(stMax[k][L], stMax[k][R - (1<<k) + 1]);
};
int Q; cin >> Q;
while (Q--) {
int L, R; cin >> L >> R;
// A = max(0, P[L-1] - min_{k in [L,R]} P[k])
int minPref = rmqMin(L, R);
int A = max(0, P[L-1] - minPref);
// B = max(0, max_{k in [L-1,R-1]} P[k] - P[R])
int B = 0;
if (L-1 <= R-1) {
int maxPref = rmqMax(L-1, R-1);
B = max(0, maxPref - P[R]);
}
cout << max(A, B) << "\n";
}
return 0;
}
