#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
const int NMAX = 5e5;
struct TreeNode {
int max_subarray_sum;
int max_prefix_sum;
int max_suffix_sum;
int sum;
TreeNode() {}
TreeNode(int value) {
max_subarray_sum = max_prefix_sum = max_suffix_sum = max(0, value);
sum = value;
}
};
struct Segment_Tree {
TreeNode segtree[4 * NMAX + 1];
TreeNode Combine(TreeNode left, TreeNode right) {
TreeNode answer;
answer.max_subarray_sum = max({left.max_subarray_sum, right.max_subarray_sum, left.max_suffix_sum + right.max_prefix_sum});
answer.max_prefix_sum = max(left.max_prefix_sum, left.sum + right.max_prefix_sum);
answer.max_suffix_sum = max(right.max_suffix_sum, right.sum + left.max_suffix_sum);
answer.sum = left.sum + right.sum;
return answer;
}
void Build(int node, int left, int right, int a[]) {
if(left == right) {
segtree[node] = TreeNode(a[left]);
return;
}
int mid = (left + right) / 2;
Build(node * 2, left, mid, a);
Build(node * 2 + 1, mid + 1, right, a);
segtree[node] = Combine(segtree[node * 2], segtree[node * 2 + 1]);
}
TreeNode Query(int node, int left, int right, int Qleft, int Qright) {
if(left >= Qleft && right <= Qright) {
return segtree[node];
}
int mid = (left + right) / 2;
if(mid >= Qright) {
return Query(node * 2, left, mid, Qleft, Qright);
}
if(mid + 1 <= Qleft) {
return Query(node * 2 + 1, mid + 1, right, Qleft, Qright);
}
TreeNode left_node = Query(node * 2, left, mid, Qleft, Qright);
TreeNode right_node = Query(node * 2 + 1, mid + 1, right, Qleft, Qright);
return Combine(left_node, right_node);
}
}segtree;
int n, q;
int a[NMAX + 1];
int Query(int left, int right) {
TreeNode answer = segtree.Query(1, 1, n, left, right);
return answer.max_subarray_sum - answer.sum;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n;
for(int i = 1; i <= n; i++) {
char s;
cin >> s;
a[i] = (s == 'C' ? 1 : -1);
}
cin >> q;
segtree.Build(1, 1, n, a);
while(q--) {
int left, right;
cin >> left >> right;
cout << Query(left, right) << '\n';
}
return 0;
}
