#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N = 5e5 + 5;
const int inf = 1e9;
struct node {
int sum, pre, suf, res;
node() {
sum = pre = suf = res = 0;
}
node(int x) {
sum = x;
pre = max(0, x);
suf = max(0, x);
res = max(0, x);
}
};
node operator + (node &a, node &b) {
node tmp;
tmp.sum = a.sum + b.sum;
tmp.pre = max(a.pre, a.sum + b.pre);
tmp.suf = max(b.suf, a.suf + b.sum);
tmp.res = max({a.pre + b.suf, a.sum + b.res, a.res + b.sum});
return tmp;
}
int n, q;
string s;
node st[N << 2];
void build(int id, int l, int r) {
if(l == r) {
if(s[l] == 'C') st[id] = node(-1);
else st[id].sum = st[id].res = st[id].pre = st[id].suf = 1;
return;
}
int m = l + r >> 1;
build(id << 1, l, m);
build(id << 1 | 1, m + 1, r);
st[id] = st[id << 1] + st[id << 1 | 1];
}
node get(int u, int v, int id = 1, int l = 1, int r = n) {
if(u > r || v < l) return node();
if(u <= l && r <= v) return st[id];
int m = l + r >> 1;
node L = get(u, v, id << 1, l, m);
node R = get(u, v, id << 1 | 1, m + 1, r);
return L + R;
}
void solve() {
cin >> n >> s >> q;
s = ' ' + s;
build(1, 1, n);
while(q--) {
int l, r; cin >> l >> r;
cout << get(l, r).res << '\n';
}
}
signed main() {
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int test = 1;
// cin >> test;
while(test--) solve();
return 0;
}
