#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
typedef long long ll;
typedef pair<int,int> ii;
typedef vector<int> vi;
typedef long double ld;
typedef tree<ii, null_type, less<ii>, rb_tree_tag, tree_order_statistics_node_update> pbds;
string s;
int n;
int del[555555];
int solve(int l, int r)
{
int cnt=0;
for(int i=l;i<=r;i++) del[i]=0;
int ans=0; int S=0; int minpref=0;
for(int i=l;i<=r;i++)
{
S+=(s[i]=='C'?1:-1);
if(s[i]=='C') cnt++;
else cnt--;
if(cnt<0)
{
del[i]=1; ans++;
cnt++;
}
}
minpref=-ans;
int positive = S - minpref;
cnt=0; int mx=0;
for(int i=r;i>=l;i--)
{
if(del[i])
{
cnt = positive; continue;
}
if(s[i]=='C') cnt++;
else cnt--;
if(cnt<0)
{
mx=max(mx,abs(cnt));
}
}
return ans+mx;
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
cin>>n; cin>>s;
int q; cin>>q;
for(int i=0;i<q;i++)
{
int l,r; cin>>l>>r; l--; r--;
cout<<solve(l,r)<<'\n';
}
}
