#include <iostream>
#include <vector>
#include <iomanip>
#include "algorithm"
#include <cmath>
#include <set>
#include <queue>
#include <random>
#include <chrono>
#include "unordered_set"
#include <unordered_map>
#include "map"
#include "numeric"
#include "climits"
#include "bitset"
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define max4(p, q, r, t) max(max(p, q), max(r, t))
#define max3(p, q, r) max(max(p, q), r)
#define testcases int t; cin>>t; while(t--)
using namespace std;
struct node {
int pref{} ;
int suff{};
int sum{};
int ans{};
node() = default;
node(int pref, int suff, int sum, int ans) : pref(pref), suff(suff), sum(sum), ans(ans) {};
};
const int N = 5e5 + 5;
node T[N << 2];
string s;
node pull(node &u, node &v) {
int pref = max(u.pref, u.sum + v.pref);
int suff = max(v.suff, v.sum + u.suff);
int sum = u.sum + v.sum;
int ans = max(u.pref + v.suff, max(u.ans + v.sum, v.ans + u.sum));
return {pref, suff, sum, ans};
}
void pull(int v, int tl, int tr) {
T[v] = pull(T[v << 1], T[v << 1 | 1]);
}
void build(int v, int tl, int tr) {
if (tl == tr) {
int val = s[tl] == 'C' ? -1 : 1;
T[v].ans = max(0, val);
T[v].pref = T[v].ans;
T[v].suff = T[v].ans;
T[v].sum = val;
return;
}
int mid = (tl + tr) >> 1;
build(v << 1, tl, mid);
build(v << 1 | 1, mid + 1, tr);
pull(v, tl, tr);
}
node get_ans(int v, int tl, int tr, int l, int r) {
if (l == tl && r == tr) {
return T[v];
}
int mid = (tl + tr) >> 1;
if (r <= mid) {
return get_ans(v << 1, tl, mid, l, r);
}
if (l > mid) {
return get_ans(v << 1 | 1, mid + 1, tr, l, r);
}
node left = get_ans(v << 1, tl, mid, l, mid);
node right = get_ans(v << 1 | 1, mid + 1, tr, mid + 1, r);
return pull(left, right);
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
cin >> s;
build(1, 0, n - 1);
int q;
cin >> q;
while (q--) {
int l, r;
cin >> l >> r;
--l, --r;
node ans = get_ans(1, 0, n - 1, l, r);
cout << ans.ans << '\n';
}
}
