#include <bits/stdc++.h>
using namespace std;
#define ar array
#define ll long long
const int inf = 2e9;
string t = "bessie";
void solve() {
int n;
cin >> n;
string s;
cin >> s;
s = "#" + s;
auto f = [&](int l, int r) {
// int ans = 0;
int pref = 0;
set<int> st;
for (int i = l; i <= r;i++) {
pref += (s[i] == 'C' ? 1 : -1);
if (pref < 0)
st.insert(i), pref = 0;
}
int suff = 0;
for (int i = r; i >= l;i--) {
if (st.count(i))
continue;
suff += (s[i] == 'C' ? 1 : -1);
if (suff < 0)
st.insert(i), suff = 0;
}
return (int)st.size();
};
int q;
cin >> q;
while (q--) {
int l, r;
cin >> l >> r;
cout << f(l, r) << "\n";
}
}
int32_t main() {
#ifdef Behruz
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios :: sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
solve();
return 0;
}
