#include <bits/stdc++.h>
using namespace std;
#define scd(t) scanf("%d", &t)
#define sclld(t) scanf("%lld", &t)
#define forr(i, j, k) for (int i = j; i < k; i++)
#define frange(i, j) forr(i, 0, j)
#define all(cont) cont.begin(), cont.end()
#define mp make_pair
#define pb push_back
#define f first
#define s second
typedef long long int lli;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<lli> vll;
typedef vector<string> vs;
typedef vector<pii> vii;
typedef vector<vi> vvi;
typedef map<int, int> mpii;
typedef set<int> seti;
typedef multiset<int> mseti;
typedef long double ld;
void usaco()
{
freopen("/media/hariaakash646/785EF1075EF0BF46/CompetitiveProgramming/input.in", "r", stdin);
// freopen("problem.out", "w", stdout);
}
struct Data {
int tot = 0;
int mi = 0;
int mil = 0;
int mir = 0;
};
template <class T>
struct SegTree
{
int size = 1, n;
vector<T> segtree;
vector<T> vec;
T def; // Assign a value
void init(int l, T defv)
{
n = l;
def = defv;
while (size < n)
size *= 2;
segtree.assign(2 * size, def);
vec.assign(size, def);
}
T operation(T x, T y)
{
T out;
out.tot = x.tot + y.tot;
out.mil = x.mil;
out.mil = min(out.mil, x.tot+y.mil);
out.mir = y.mir;
out.mir = min(out.mir, x.mir + y.tot);
// out.mi = min(x.mi, y.mi);
// out.mi = min(out.mi, x.mir + y.mil);
out.mi = min(min(x.mi+y.tot, y.mi+x.tot), x.mil + y.mir);
return out;
}
void recalculate(int x)
{
segtree[x] = operation(segtree[2 * x + 1], segtree[2 * x + 2]);
}
void build(int x, int l, int r)
{
if (l == r)
{
segtree[x] = vec[l];
return;
}
int mid = (l + r) / 2;
build(2 * x + 1, l, mid);
build(2 * x + 2, mid + 1, r);
recalculate(x);
}
void build()
{
build(0, 0, size - 1);
}
void set(int id, T val)
{
vec[id] = val;
}
void update(int x, int l, int r, int id, T val)
{
if (l == r)
{
segtree[x] = val;
return;
}
int mid = (l + r) / 2;
if (id <= mid)
{
update(2 * x + 1, l, mid, id, val);
}
else
{
update(2 * x + 2, mid + 1, r, id, val);
}
recalculate(x);
}
void update(int id, T val)
{
update(0, 0, size - 1, id, val);
}
T query(int x, int l, int r, int lx, int rx)
{
if (lx > r || rx < l)
{
return def;
}
if (lx <= l && r <= rx)
{
return segtree[x];
}
int mid = (l + r) / 2;
T v1 = query(2 * x + 1, l, mid, lx, rx);
T v2 = query(2 * x + 2, mid + 1, r, lx, rx);
return operation(v1, v2);
}
T query(int lx, int rx)
{
return query(0, 0, size - 1, lx, rx);
}
};
int main() {
// usaco();
int n;
scd(n);
string str;
cin >> str;
SegTree<Data> segtree;
Data tmp;
segtree.init(n, tmp);
frange(i, n) {
if(str[i] == 'C') {
tmp.tot = 1;
tmp.mi = tmp.mil = tmp.mir = 0;
segtree.set(i, tmp);
}
else {
tmp.tot = tmp.mi = tmp.mil = tmp.mir = -1;
segtree.set(i, tmp);
}
}
segtree.build();
int q;scd(q);
frange(_, q) {
int l, r;
scd(l);
scd(r);
l--;
r--;
printf("%d\n", -segtree.query(l, r).mi);
}
}
