#include <bits/stdc++.h>
#pragma GCC optimize("O3")
using namespace std;
#define ll long long
#define pb push_back
#define fr first
#define sc second
#define MAX ((ll)(1e9+100))
#define MX ((ll)(1e6+100))
#define ARRS ((ll)(2e6+100))
#define HS ((ll)(233))
#define MOD ((ll)(1e9+7))
#define EP ((double)(1e-9))
#define LG 21
#define mul(a,b) a=((a)*(b))%MOD
using namespace std;
ll n;
ll m,k;
vector<ll> v[ARRS];
ll f[ARRS];
ll a[ARRS];
ll sm[ARRS];
ll ct[ARRS];
ll sum(ll l,ll r){
return sm[r]-sm[l-1];
}
struct node{
node *L,*R;
ll u,d,s,sm;
node(){
L=R=NULL;
u=0;
d=0;
s=0;
sm=0;
}
void updt(){
node a=*L;
node b=*R;
sm=a.sm+b.sm;
///////
u=max(a.u,b.u+a.sm);
d=max(b.d,a.d+b.sm);
b.u=max(0ll,a.sm+b.u-a.u);
a.d=max(0ll,b.sm+a.d-b.d);
s=min(b.s,b.u)+
min(a.s,a.d)+
max(0ll,min(b.u-b.s,a.d-a.s));
}
};
node join(node a,node b){
node x;
x.sm=a.sm+b.sm;
///////
x.u=max(a.u,b.u+a.sm);
x.d=max(b.d,a.d+b.sm);
b.u=max(0ll,a.sm+b.u-a.u);
a.d=max(0ll,b.sm+a.d-b.d);
x.s=min(b.s,b.u)+
min(a.s,a.d)+
max(0ll,min(b.u-b.s,a.d-a.s));
return x;
}
void init(ll l,ll r,node *& x){
if(!x)x=new node();
if(l==r-1){
if(a[l]==1){
x->u=0;
x->d=0;
x->s=0;
x->sm=-1;
}
else {
x->u=1;
x->d=1;
x->s=1;
x->sm=1;
}
return;
}
init(l,l+r>>1,x->L);
init(l+r>>1,r,x->R);
x->updt();
// cout<<l<<" "<<r<<" "<<x->u<<" "<<x->d<<" "<<x->s<<" "<<x->sm<<endl;
}
node pas;
ll wl,wr;
void quer(ll l,ll r,node *& x){
if(wr<l||r-1<wl)return;
if(wl<=l&&r-1<=wr){
pas=join(pas,*x);
return;
}
quer(l,l+r>>1,x->L);
quer(l+r>>1,r,x->R);
}
node *rt=NULL;
int main(){
#ifdef KHOKHO
freopen("in.in","r",stdin);
freopen("out.out","w",stdout);
#endif // KHOKHO
ios::sync_with_stdio(0);
ll n;
string s;
cin>>n>>s;
for(int i=1; i<=n; i++){
if(s[i-1]=='C')a[i]=1;
else a[i]=-1;
}
ll q,l,r;
init(1,n+1,rt);
cin>>q;
while(q--){
cin>>wl>>wr;
pas=*(new node());
quer(1,n+1,rt);
cout<<pas.u+pas.d-pas.s<<endl;
}
}
