#include<bits/stdc++.h>
using namespace std;
#define int long long
struct isi{
int sum,pref,suf,ans;
};
string s;
vector<isi>st;
isi merg(isi a,isi b){
// cout<<a.sum<<" "<<a.pref<<" "<<a.suf<<" "<<a.ans<<endl;
// cout<<b.sum<<" "<<b.pref<<" "<<b.suf<<" "<<b.ans<<endl;
isi akh;
akh.sum=a.sum+b.sum;
akh.pref=min(a.sum+b.pref,a.pref);
akh.suf=min(b.sum+a.suf,b.suf);
akh.ans=max({a.ans-(b.sum),b.ans-(a.sum),-(a.pref+b.suf)});
//cout<<akh.sum<<" "<<akh.pref<<" "<<akh.suf<<" "<<akh.ans<<endl;
return akh;
}
void build(int idx,int l,int r){
if(l==r){
if(s[l]=='C'){
st[idx]={1,0,0,0};
}
else{
st[idx]={-1,-1,-1,1};
}
return;
}
int mid=(l+r)/2;
build(2*idx,l,mid);
build(2*idx+1,mid+1,r);
st[idx]=merg(st[2*idx],st[2*idx+1]);
}
isi query(int idx,int l,int r,int posl,int posr){
if(l>=posl && r<=posr)return st[idx];
if(l>posr || r<posl)return {0,0,0,0};
int mid=(l+r)/2;
return merg(query(2*idx,l,mid,posl,posr),query(2*idx+1,mid+1,r,posl,posr));
}
signed main(){
int n;
cin>>n;
cin>>s;
s="."+s;
st=vector<isi>(4*n+1);
build(1,1,n);
int qu;
cin>>qu;
while(qu--){
int l,r;
cin>>l>>r;
cout<<query(1,1,n,l,r).ans<<endl;
}
}
