#include <bits/stdc++.h>
using namespace std;
const int N = 5e5 + 5;
struct Data{
int sum, prefix, suffix, ans;
}ST[4 * N];
int n, q, a[N];
Data M(Data A, Data B) {
Data res;
res.sum = A.sum + B.sum;
res.prefix = max(A.prefix, A.sum + B.prefix);
res.suffix = max(B.suffix, B.sum + A.suffix);
res.ans = max({A.prefix + B.suffix, A.ans + B.sum, A.sum + B.ans});
return res;
}
void build(int id, int l, int r) {
if(l == r) {
if(a[l] == 1) ST[id] = {-1, 0, 0, 0};
else ST[id] = {1, 1, 1, 1};
return;
}
int mid = (l + r) / 2;
build(id * 2, l, mid);
build(id * 2 + 1, mid + 1, r);
ST[id] = M(ST[id * 2], ST[id * 2 + 1]);
}
Data get(int id, int l, int r, int u, int v) {
if(v < l || u > r) return {0, 0, 0, 0};
if(u <= l && v >= r) return ST[id];
int mid = (l + r) / 2;
return M(get(id * 2, l, mid, u, v), get(id * 2 + 1, mid + 1, r, u, v));
}
void Solve() {
cin >> n;
for(int i = 1; i <= n; i++) {
char c; cin >> c;
if(c == 'C') a[i] = 1;
else a[i] = -1;
}
cin >> q;
build(1, 1, n);
while(q--) {
int l, r; cin >> l >> r;
cout << get(1, 1, n, l, r).ans << '\n';
}
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
Solve();
}
