#include <bits/stdc++.h>
using namespace std;
#define int long long
#define mid ((l+r)/2)
#define ls (2*cr)
#define rs (2*cr+1)
struct segmentTree{
struct data{
int pref, suf, sum, sol;
};
data join(data a, data b){
data ret;
ret.pref=max(a.pref, a.sum+b.pref);
ret.suf=max(a.suf+b.sum, b.suf);
ret.sum=a.sum+b.sum;
ret.sol=max({a.pref+b.suf, a.sol+b.sum, a.sum+b.sol});
return ret;
}
int n;
vector<data> v;
segmentTree(int _n){
n=_n;
v.resize(4*n+2);
}
void build(string &val, int l, int r, int cr){
if(l==r){
if(val[l]=='C') v[cr].pref=0, v[cr].suf=0, v[cr].sol=0, v[cr].sum=-1;
else v[cr].pref=1, v[cr].suf=1, v[cr].sol=1, v[cr].sum=1;
}
else{
build(val, l, mid, ls);
build(val, mid+1, r, rs);
v[cr]=join(v[ls], v[rs]);
}
}
void build(string &val){
build(val, 1, n, 1);
}
data query(int ql, int qr, int l, int r, int cr){
if(ql==l&&qr==r){
return v[cr];
}
else{
if(qr<=mid) return query(ql, qr, l, mid, ls);
if(mid<ql) return query(ql, qr, mid+1, r, rs);
return join(query(ql, mid, l, mid, ls), query(mid+1, qr, mid+1, r, rs));
}
}
int query(int l, int r){
return query(l, r, 1, n, 1).sol;
}
};
#undef mid
#undef ls
#undef rs
int32_t main(){
int n;
cin>>n;
string s;
cin>>s;
s='$'+s;
segmentTree aint=segmentTree(n);
aint.build(s);
int q;
cin>>q;
while(q--){
int l, r;
cin>>l>>r;
cout<<aint.query(l, r)<<"\n";
}
return 0;
}
