//Huyduocdithitp
#include <bits/stdc++.h>
typedef int ll;
#define pii pair<ll, ll>
#define MP make_pair
#define fi first
#define se second
#define TASK "connect"
#define faster ios_base::sync_with_stdio(false);cin.tie(NULL);
#define N 500005
#define LOG 18
#define endl '\n'
using namespace std;
ll n, q;
string s;
struct Node {
ll L, R, S, A;
} st[4 * N];
Node cb(Node u, Node v) {
Node w;
w.L = max(u.L, u.S + v.L);
w.R = max(v.R, v.S + u.R);
w.S = u.S + v.S;
w.A = max({u.A + v.S, u.S + v.A, u.L + v.R});
return w;
}
void build(ll id, ll l, ll r) {
if (l == r) {
if (s[l] == 'C') {
st[id] = {0, 0, -1, 0};
}
else {
st[id] = {1, 1, 1, 1};
}
return;
}
ll mid = (l + r) / 2;
build(id * 2, l, mid);
build(id * 2 + 1, mid + 1, r);
st[id] = cb(st[id * 2], st[id * 2 + 1]);
}
Node get(ll id, ll l, ll r, ll L, ll R) {
if (l > R || r < L) return {0, 0, 0, 0};
if (L <= l && r <= R) return st[id];
ll mid = (l + r) / 2;
return cb(get(id * 2, l, mid, L, R), get(id * 2 + 1, mid + 1, r, L, R));
}
signed main(void) {
faster;
cin >> n;
cin >> s;
cin >> q;
s = '*' + s;
build(1, 1, n);
for (int i = 1; i <= q; i ++) {
ll l, r;
cin >> l >> r;
cout << get(1, 1, n, l, r).A << endl;
}
return 0;
}
