#include <bits/stdc++.h>
#define int long long
#define pii pair<int, int>
#define ff first
#define ss second
const int inf = 3e18;
using namespace std;
using ld = long double;
/*
struct seggy
{
int n;
vector<int> tree;
seggy(int sz)
{
n = sz;
tree.resize(4*n,0);
}
int query(int l,int r,int L,int R,int idx)
{
if (l>R||r<L)return 0ll;
if (l>=L&&r<=R)return tree[idx];
int mid = l+r>>1;
return query(l,mid,L,R,2*idx)+query(mid+1,r,L,R,2*idx+1);
}
int query(int l,int r)
{
return query(0,n-1,l,r,1);
}
void update(int l,int r,int i,int x,int idx)
{
if (l>i||r<i)return;
if(l==r)
{
tree[idx] = x;
return;
}
int mid = l+r>>1;
update(l,mid,i,x,2*idx);
update(mid+1,r,i,x,2*idx+1);
tree[idx] = tree[2*idx]+tree[2*idx+1];
}
void update(int i,int x)
{
update(0,n-1,i,x,1);
}
};
*/
struct lijen
{
int n;
vector<int> tree,lazy;
lijen(int sz)
{
n = sz;
tree.resize(4*n,0);
lazy.resize(4*n,0);
}
void pass(int l,int r,int idx)
{
if (lazy[idx]==0)return;
tree[idx]+=lazy[idx];
if(l!=r)
{
lazy[2*idx]+=lazy[idx];
lazy[2*idx+1]+=lazy[idx];
}
lazy[idx] = 0;
}
int query(int l,int r,int L,int R,int idx)
{
pass(l,r,idx);
if (l>R||r<L)return inf;
if (l>=L&&r<=R)return tree[idx];
int mid = l+r>>1;
return min(query(l,mid,L,R,2*idx),query(mid+1,r,L,R,2*idx+1));
}
int query(int l,int r)
{
return query(0,n-1,l,r,1);
}
void update(int l,int r,int L,int R,int x,int idx)
{
pass(l,r,idx);
if (l>R||r<L)return;
if (l>=L&&r<=R)
{
lazy[idx]+=x;
pass(l,r,idx);
return;
}
int mid = l+r>>1;
update(l,mid,L,R,x,2*idx);
update(mid+1,r,L,R,x,2*idx+1);
tree[idx] = min(tree[2*idx],tree[2*idx+1]);
}
void update(int l,int r,int x)
{
update(0,n-1,l,r,x,1);
}
};
void solve()
{
int n;
cin >> n;
string s;
cin >> s;
vector<int> v(n,-1);
for (int i = 0; i < n; i++)
if (s[i]=='C')
v[i] +=2;
int q;
cin >> q;
vector<array<int,3>> quers(q);
for (int i = 0; i < q; i++)
cin >> quers[i][0]>> quers[i][1],quers[i][2] = i;
sort(quers.begin(),quers.end());
vector<int> ans(q);
for (auto&a:quers)
a[0]--,a[1]--;
vector<int> pref(n),suf(n);
pref[0] = v[0];
for (int i = 1; i < n; i++)
pref[i] = v[i]+pref[i-1];
suf[n-1] = v[n-1];
for (int i = n-2; i >= 0; i--)
suf[i] = suf[i+1]+v[i];
lijen mile(n),nane(n);
for (int i = 0; i < n; i++)
mile.update(i,i,suf[i]),nane.update(i,i,pref[i]);
map<int,int> idx;
map<int,vector<int>> idxs;
for (int i = 0; i < n; i++)
idxs[pref[i]].push_back(i);
for (int i = -n; i <= n; i++)
idxs[i].push_back(n);
for (int i = -1; i >= -n; i--)
if (idxs[i].size()>1)
mile.update(0,idxs[i][0],1);
int sum = 0;
int j = 0;
auto print = [&]()
{
for (int i = 0; i < n; i++)
{
cout << mile.query(i,i) << ' ';
}
cout << '\n';
for (int i = 0; i < n; i++)
cout << nane.query(i,i) << ' ';
cout << "\n\n";
};
for (int i = 0; i < n; i++)
{
//print();
while (j < q && quers[j][0] == i)
{
int l = quers[j][0],r = quers[j][1];
ans[quers[j][2]] = max(0ll,-(nane.query(l,r)-(l>0?pref[l-1]:0)))
+ max(0ll,-(mile.query(l,r)-(r<n-1?mile.query(r+1,r+1):0)));
j++;
}
if (pref[i] < sum)
{
int p = idx[pref[i]];
mile.update(idxs[pref[i]][p],idxs[pref[i]][p+1]-1,1);
}
idx[pref[i]]++;
if (idx[sum] >= idxs[sum].size()-1)continue;
int val = idxs[sum][idx[sum]];
if (v[i]<0)
mile.update(0,val,-1);
else
mile.update(0,val,1);
sum+=v[i];
}
for(int x : ans)
cout << x << '\n';
}
signed main()
{
ios::sync_with_stdio(0);
int t = 1;
// cin >> t;
while (t--)
solve();
}
