#include <bits/stdc++.h>
#define DIM 500010
#define INF 2000000000
using namespace std;
int v[DIM],ans[DIM],s[DIM];
char c[DIM];
int n,q,i,x,y,sol,sol2,sum,poz,k;
struct segment_tree{
int sum,suf,poz;
} aint[DIM*4];
vector <pair <int,int> > qry[DIM];
void build (int nod, int st, int dr){
if (st == dr){
aint[nod].sum = aint[nod].suf = v[st];
aint[nod].poz = st;
return;
}
int mid = (st+dr)>>1;
build (nod<<1,st,mid);
build ((nod<<1)|1,mid+1,dr);
int fiu_st = nod<<1, fiu_dr = (nod<<1)|1;
aint[nod].sum = aint[fiu_st].sum + aint[fiu_dr].sum;
if (aint[fiu_dr].suf <= aint[fiu_dr].sum + aint[fiu_st].suf){
aint[nod].suf = aint[fiu_dr].suf;
aint[nod].poz = aint[fiu_dr].poz;
} else {
aint[nod].suf = aint[fiu_dr].sum + aint[fiu_st].suf;
aint[nod].poz = aint[fiu_st].poz;
}
}
void update (int nod, int st, int dr, int poz, int val){
if (st == dr){
aint[nod].sum = aint[nod].suf = val;
return;
}
int mid = (st+dr)>>1;
if (poz <= mid)
update (nod<<1,st,mid,poz,val);
else update ((nod<<1)|1,mid+1,dr,poz,val);
int fiu_st = nod<<1, fiu_dr = (nod<<1)|1;
aint[nod].sum = aint[fiu_st].sum + aint[fiu_dr].sum;
if (aint[fiu_dr].suf <= aint[fiu_dr].sum + aint[fiu_st].suf){
aint[nod].suf = aint[fiu_dr].suf;
aint[nod].poz = aint[fiu_dr].poz;
} else {
aint[nod].suf = aint[fiu_dr].sum + aint[fiu_st].suf;
aint[nod].poz = aint[fiu_st].poz;
}
}
void query (int nod, int st, int dr, int x, int y){
if (x <= st && dr <= y){
if (sum + aint[nod].suf < sol){
sol = sum + aint[nod].suf;
poz = aint[nod].poz;
}
sum += aint[nod].sum;
return;
}
int mid = (st+dr)>>1;
if (y > mid)
query ((nod<<1)|1,mid+1,dr,x,y);
if (x <= mid)
query (nod<<1,st,mid,x,y);
}
int main (){
//ifstream cin ("election.in");
//ofstream cout ("election.out");
cin>>n>>c+1;
for (i=1;i<=n;i++){
if (c[i] == 'C')
v[i] = 1;
else v[i] = -1;
}
build (1,1,n);
cin>>q;
for (i=1;i<=q;i++){
cin>>x>>y;
qry[x].push_back(make_pair(y,i));
}
for (i=n;i;i--){
if (v[i] == 1){
if (k){
update (1,1,n,s[k],v[s[k]]);
k--;
}
} else {
s[++k] = i;
update (1,1,n,i,0);
}
if (i == 1907)
i = 1907;
for (auto it : qry[i]){
int y = it.first;
sol = INF, sum = 0, poz = 0;
query (1,1,n,i,it.first);
/// primul mai mic sau egal cu y din stiva
int st = 1, dr = k, sol_st = k+1;
while (st <= dr){
int mid = (st+dr)>>1;
if (s[mid] <= y){
sol_st = mid;
dr = mid-1;
} else st = mid+1;
}
ans[it.second] = k - sol_st + 1 + max(0,-sol);
}
}
for (i=1;i<=q;i++)
cout<<ans[i]<<"\n";
return 0;
}
