#include <bits/stdc++.h>
/*
Phia ben kia dai duong cung chi co
Bo cat nang niu bien thoi
*/
using namespace std;
using ll = long long;
#define int long long
#define pii pair<ll, ll>
#define fi first
#define se second
const ll N = 2e5 + 5, inf = 1e18, mod = 1e9 + 7, block = 320, lim = 19;
int n;
char a[N];
int q;
struct ST {
struct item {
int L, R, sum, ans;
item() : L(0), R(0), sum(0), ans(0) {}
};
vector <item> st;
ST (int _n) {
st.assign(4 * (_n + 1), item());
}
item combine(item &A, item &B) {
item C;
C.L = max(A.L, A.sum + B.L);
C.R = max(B.R, A.R + B.sum);
C.sum = A.sum + B.sum;
C.ans = max({A.ans + B.sum, A.sum + B.ans, A.L + B.R});
return C;
}
void update(int i, int l, int r, int pos, char val) {
if (l == r) {
item tmp;
if (val == 'C') {
tmp.L = 0, tmp.R = 0, tmp.sum = -1, tmp.ans = 0;
}
else {
tmp.L = 1, tmp.R = 1, tmp.sum = 1, tmp.ans = 1;
}
st[i] = tmp;
return;
}
int mid = (l + r) / 2;
if (pos <= mid) update(2 * i, l, mid, pos, val);
else update(2 * i + 1, mid + 1, r, pos, val);
st[i] = combine(st[2 * i], st[2 * i + 1]);
}
item get(int i, int l, int r, int u, int v) {
if (u > r || v < l) return item();
if (u <= l && r <= v) return st[i];
int mid = (l + r) / 2;
auto L = get(2 * i, l, mid, u, v);
auto R = get(2 * i + 1, mid + 1, r, u, v);
return combine(L, R);
}
} st(N);
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
if (fopen(".inp", "r")) {
freopen(".inp", "r", stdin);
freopen(".out", "w", stdout);
}
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> a[i];
st.update(1, 1, n, i, a[i]);
}
cin >> q;
while(q-- > 0) {
int l, r;
cin >> l >> r;
cout << st.get(1, 1, n, l, r).ans << '\n';
}
return 0;
}
