#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e9 + 7;
int N;
vector<int> P, PR;
vector<int> segF, segB;
void buildF(int v, int l, int r) {
if(l == r){
segF[v] = P[l];
}
else{
int m = (l + r) / 2;
buildF(v * 2, l, m);
buildF(v * 2 + 1, m + 1, r);
segF[v] = min(segF[v * 2], segF[v * 2 + 1]);
}
}
int queryF(int v, int l, int r, int ql, int qr) {
if(ql > r || qr < l) return INT_MAX;
if(ql <= l && r <= qr) return segF[v];
int m = (l + r) / 2;
return min(queryF(v * 2, l, m, ql, qr),
queryF(v * 2 + 1, m + 1, r, ql, qr)
);
}
void buildB(int v, int l, int r) {
if(l == r) {
segB[v] = PR[l];
}
else{
int m = (l + r) / 2;
buildB(v * 2, l, m);
buildB(v * 2 + 1, m + 1, r);
segB[v] = min(segB[v * 2], segB[v * 2 + 1]);
}
}
int queryB(int v, int l, int r, int ql, int qr) {
if(ql > r || qr < l) return INT_MAX;
if(ql <= l && r <= qr) return segB[v];
int m = (l + r) / 2;
return min(queryB(v * 2, l, m, ql, qr),
queryB(v * 2 + 1, m + 1, r, ql, qr)
);
}
void solve(){
cin>>N;
string S;
cin>>S;
P.assign(N + 1, 0);
PR.assign(N + 2, 0);
for(int i = 1; i <= N; i++){
P[i] = P[i - 1] + (S[i - 1] == 'C' ? 1 : -1);
}
for(int i = N; i >= 1; i--){
PR[N - i + 1] = PR[N - i] + (S[i - 1] == 'C' ? 1 : -1);
}
segF.assign(4 * N, INT_MAX);
segB.assign(4 * N, INT_MAX);
buildF(1, 1, N);
buildB(1, 1, N);
int Q;
cin>>Q;
while(Q--){
int L, R;
cin>>L>>R;
int baseF = P[L - 1];
int mnF = queryF(1, 1, N, L, R);
int delF = max(0, baseF - mnF);
int Lp = N - R + 1;
int Rp = N - L + 1;
int baseB = PR[Lp - 1];
int mnB = queryB(1, 1, N, Lp, Rp);
int delB = max(0, baseB - mnB);
cout<<max(delF, delB)<<'\n';
}
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
int t = 1;
//cin>>t;
while(t--){
solve();
}
}
