#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e18;
const int MOD = 1e9 + 7;
struct mi {
int v;
explicit operator int() const { return v; }
mi() { v = 0; }
mi(long long _v) : v(_v % MOD) { v += (v < 0) * MOD; }
};
mi &operator+=(mi &a, mi b) {
if ((a.v += b.v) >= MOD) a.v -= MOD;
return a;
}
mi &operator-=(mi &a, mi b) {
if ((a.v -= b.v) < 0) a.v += MOD;
return a;
}
mi operator+(mi a, mi b) { return a += b; }
mi operator-(mi a, mi b) { return a -= b; }
mi operator*(mi a, mi b) { return mi((long long)a.v * b.v); }
mi &operator*=(mi &a, mi b) { return a = a * b; }
mi pow(mi a, long long p) {
assert(p >= 0);
return p == 0 ? 1 : pow(a * a, p / 2) * (p & 1 ? a : 1);
}
mi inv(mi a) {
assert(a.v != 0);
return pow(a, MOD - 2);
}
mi operator/(mi a, mi b) { return a * inv(b); }
template <class T>
void print(vector<T>& arr, bool __endl = true){
for (int i = 0; i < arr.size(); i ++) cout << arr[i] << ' ';
if (__endl)
cout << '\n';
}
template <class T>
void input(vector<T>& arr){
for (int i = 0; i < arr.size(); i ++) cin >> arr[i];
}
struct SegTreeNode{
int t_count = 0, c_count = 0, diff = 0;
SegTreeNode(){}
SegTreeNode(int t, int c, int d) : t_count(t), c_count(c), diff(d) {}
};
struct SegTree_LR{
vector<SegTreeNode> tree;
int n;
SegTree_LR(string &s){
tree.resize(4 * s.size());
n = s.size();
build(0, 0, n - 1, s);
}
void build(int v, int l, int r, string &s){
if (l == r){
if (s[l] == 'C') tree[v].c_count++;
else tree[v].t_count ++;
tree[v].diff = tree[v].t_count - tree[v].c_count;
return;
}
int m = (l + r) / 2;
build(2 * v + 1, l, m, s);
build(2 * v + 2, m + 1, r, s);
tree[v].t_count = tree[2 * v + 1].t_count + tree[2 * v + 2].t_count;
tree[v].c_count = tree[2 * v + 1].c_count + tree[2 * v + 2].c_count;
tree[v].diff = max(tree[2 * v + 1].diff, tree[2 * v + 2].diff + tree[2 * v + 1].t_count - tree[2 * v + 1].c_count);
}
SegTreeNode query(int v, int tl, int tr, int l, int r){
if (tl == l && tr == r) return tree[v];
int m = (tl + tr) / 2;
if (r <= m) return query(2 * v + 1, tl, m, l, r);
if (l > m) return query(2 * v + 2, m + 1, tr, l, r);
SegTreeNode left = query(2 * v + 1, tl, m, l, m);
SegTreeNode right = query(2 * v + 2, m + 1, tr, m + 1, r);
SegTreeNode ret = SegTreeNode();
ret.t_count = left.t_count + right.t_count;
ret.c_count = left.c_count + right.c_count;
ret.diff = max(left.diff, right.diff + left.t_count - left.c_count);
return ret;
}
int query(int l, int r){
return max(0, query(0, 0, n - 1, l, r).diff);
}
};
struct SegTree_RL{
vector<SegTreeNode> tree;
int n;
SegTree_RL(string &s){
tree.resize(4 * s.size());
n = s.size();
build(0, 0, n - 1, s);
}
void build(int v, int l, int r, string &s){
if (l == r){
if (s[l] == 'C') tree[v].c_count++;
else tree[v].t_count ++;
tree[v].diff = tree[v].t_count - tree[v].c_count;
return;
}
int m = (l + r) / 2;
build(2 * v + 1, l, m, s);
build(2 * v + 2, m + 1, r, s);
tree[v].t_count = tree[2 * v + 1].t_count + tree[2 * v + 2].t_count;
tree[v].c_count = tree[2 * v + 1].c_count + tree[2 * v + 2].c_count;
tree[v].diff = max(tree[2 * v + 2].diff, tree[2 * v + 1].diff + tree[2 * v + 2].t_count - tree[2 * v + 2].c_count);
}
SegTreeNode query(int v, int tl, int tr, int l, int r){
if (tl == l && tr == r) return tree[v];
int m = (tl + tr) / 2;
if (r <= m) return query(2 * v + 1, tl, m, l, r);
if (l > m) return query(2 * v + 2, m + 1, tr, l, r);
SegTreeNode left = query(2 * v + 1, tl, m, l, m);
SegTreeNode right = query(2 * v + 2, m + 1, tr, m + 1, r);
SegTreeNode ret = SegTreeNode();;
ret.t_count = left.t_count + right.t_count;
ret.c_count = left.c_count + right.c_count;
ret.diff = max(right.diff, left.diff + right.t_count - right.c_count);
return ret;
}
int query(int l, int r){
return max(0, query(0, 0, n - 1, l, r).diff);
}
};
// #define with_testcases
void t_main(signed __T){
int n;
cin >> n;
string s;
cin >> s;
SegTree_LR sglr(s);
SegTree_RL sgrl(s);
int q;
cin >> q;
while (q --){
int l, r;
cin >> l >> r;
--l; -- r;
// cout << l << ' ' << r << '\n';
// cout << sglr.query(l, r) << ' ' << sgrl.query(l, r) << '\n';
cout << max(sglr.query(l, r), sgrl.query(l, r)) << '\n';
}
}
signed main(){
cin.tie(nullptr) -> sync_with_stdio(false);
int t = 1;
#ifdef with_testcases
cin >> t;
#endif
for (int i = 1; i <= t; i ++) {
t_main(i);
// cout << '\n';
}
}
