#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int MAX_N = 200005;
vector<pair<ll,ll>> treePref, treeSuf;
pair<ll,ll> query(int x, int lx, int rx, int l, int r) {
if(lx > r or rx < l) return {0, 0};
if(lx >= l and rx <= r) return treePref[x];
int mid = (lx+rx)/2;
pair<ll,ll> left = query(2*x, lx, mid, l, r);
pair<ll,ll> right = query(2*x+1, mid+1, rx, l, r);
return {left.first+right.first, max(left.second, left.first+right.second)};
}
pair<ll,ll> Query(int x, int lx, int rx, int l, int r) {
if(lx > r or rx < l) return {0, 0};
if(lx >= l and rx <= r) return treeSuf[x];
int mid = (lx+rx)/2;
pair<ll,ll> left = Query(2*x, lx, mid, l, r);
pair<ll,ll> right = Query(2*x+1, mid+1, rx, l, r);
return {left.first+right.first, max(right.second, right.first+left.second)};
}
void solve() {
int n; cin >> n;
string s; cin >> s;
vector<int>a;
for(int i=0; i<n; i++) {
if(s[i] == 'C') a.push_back(-1);
else a.push_back(1);
}
while(__builtin_popcount(n) != 1) {
a.push_back(0);
n++;
}
treePref.resize(2*n);
treeSuf.resize(2*n);
for(int i=0; i<n; i++) {
treePref[n+i] = {a[i], a[i]};
treeSuf[n+i] = {a[i], a[i]};
}
for(int i=n-1; i>0; i--) {
treePref[i].first = treePref[2*i].first + treePref[2*i+1].first;
treePref[i].second = max(treePref[2*i].second, treePref[2*i].first+treePref[2*i+1].second);
treeSuf[i].first = treeSuf[2*i].first + treeSuf[2*i+1].first;
treeSuf[i].second = max(treeSuf[2*i+1].second, treeSuf[2*i+1].first + treeSuf[2*i].second);
}
int q; cin >> q;
while(q--) {
int l,r;
cin >> l >> r;
l--; r--;
cout << max(query(1,0,n-1,l,r).second,Query(1,0,n-1,l,r).second) << endl;
}
}
int main() {
int t=1;
while(t--)
solve();
}
