#include <bits/stdc++.h>
using namespace std;
struct Node {
int ans;
int maxp;
int maxs;
int sum;
Node operator+(Node second) {
Node ret;
if (ans == INT_MIN and second.ans == INT_MIN) {
return {INT_MIN, 0, 0, 0};
} else if (second.ans == INT_MIN) {
return {ans, maxp, maxs, sum};
} else if (ans == INT_MIN) {
return {second.ans, second.maxp, second.maxs, second.sum};
}
ret.ans = max(max(sum + second.ans, ans + second.sum), maxp + second.maxs);
ret.sum = sum + second.sum;
ret.maxp = max(maxp, sum + second.maxp);
ret.maxs = max(second.maxs, second.sum + maxs);
return ret;
}
};
int n;
vector<char> el(1e6);
vector<Node> segtree(1e6);
unordered_map<char, int> mp = {make_pair('C', -1), make_pair('T', 1)};
void build(int index = 1, int l = 0, int r = n - 1) {
if (l == r) {
if (el[l] == 'T') {
segtree[index] = {1, 1, 1, 1};
} else {
segtree[index] = {0, 0, 0, -1};
}
return;
}
int mid = (l + r) / 2;
build(index * 2, l, mid);
build(index * 2 + 1, mid + 1, r);
segtree[index] = segtree[index * 2] + segtree[index * 2 + 1];
}
Node query(int ql, int qr, int index = 1, int l = 0, int r = n - 1) {
if (l > qr or r < ql) {
return {INT_MIN, 0, 0, 0};
}
if (l >= ql and r <= qr) {
return segtree[index];
}
int mid = (l + r) / 2;
return query(ql, qr, index * 2, l, mid) + query(ql, qr, index * 2 + 1, mid + 1, r);
}
int main() {
cin >> n;
for (int i = 0; i < n; ++i) cin >> el[i];
build();
int q;
cin >> q;
while (q--) {
int a, b;
cin >> a >> b;
--a; --b;
cout << query(a, b).ans << endl;
}
}
