#include "bits/stdc++.h"
using namespace std;
#define mod 998244353
#define ll long long
#define N 24
#define maxn 200005
void solve(){
int n;
cin>>n;
string s;
cin>>s;
int sq=sqrt(n);
int pref[n+5],prefg[n+5];
int cur=0,x=1e9;
for(int i=0; i<s.size(); i++){
if(s[i]=='C') cur++;
else cur--;
x=min(x,cur);
pref[i]=cur;
if(i%sq==(sq-1)){
prefg[i/sq]=x;
x=1e9;
}
}
cur=0;
x=1e9;
int suf[n+5],sufg[n+5];
for(int i=s.size()-1; i>=0; i--){
if(s[i]=='C') cur++;
else cur--;
x=min(x,cur);
suf[i]=cur;
if(i%sq==0){
sufg[i/sq]=x;
x=1e9;
}
}
int q;
cin>>q;
while(q--){
int l,r;
cin>>l>>r;
int mn=1e9;
for(int i=l-1; i<r; i++){
if(i%sq==0 and i+sq<=r){
mn=min(mn,prefg[i/sq]);
i=i+sq-1;
continue;
}
mn=min(mn,pref[i]);
}
if(l>1){
mn-=pref[l-2];
}
int ans=mn;
mn=1e9;
for(int i=l-1; i<r; i++){
if(i%sq==0 and i+sq<=r){
mn=min(mn,sufg[i/sq]);
i=i+sq-1;
continue;
}
mn=min(mn,suf[i]);
}
if(r<n){
mn-=suf[r];
}
ans=min(ans,mn);
cout<<abs(min(ans,0))<<'\n';
}
}
int main(){
// freopen("in.txt","w",stdout);
// freopen("out.txt","r",stdin);
ios_base::sync_with_stdio(0); cin.tie(0);
ll t=1;
// cin>>t;
while(t--) solve();
}
