#include <bits/stdc++.h>
#define int long long
using namespace std;
const int N=500010;
int n, q;
string t;
class seg {
public:
void init() {init(1, 1, n);}
int query(int l, int r) {return query(1, 1, n, l, r).v;}
private:
struct Data {int l, r, s, v;};
Data tree[4*N];
Data Merge(Data a, Data b) {
Data ret;
ret.l=max(a.l, -a.s+b.l);
ret.r=max(b.r, a.r-b.s);
ret.s=a.s+b.s;
ret.v=max({a.v-b.s, b.v-a.s, a.l+b.r});
return ret;
}
void init(int node, int s, int e) {
if(s==e) {
if(t[s-1]=='C') tree[node]={0, 0, 1, 0};
else tree[node]={1, 1, -1, 1};
return;
}
int lch=2*node, rch=lch+1, m=(s+e)/2;
init(lch, s, m), init(rch, m+1, e);
tree[node]=Merge(tree[lch], tree[rch]);
}
Data query(int node, int s, int e, int l, int r) {
if(l<=s && e<=r) return tree[node];
int lch=2*node, rch=lch+1, m=(s+e)/2;
if(r<=m) return query(lch, s, m, l, r);
if(l>m) return query(rch, m+1, e, l, r);
return Merge(query(lch, s, m, l, r), query(rch, m+1, e, l, r));
}
}T;
signed main() {
ios_base::sync_with_stdio(0); cin.tie(0);
cin>>n>>t;
T.init();
cin>>q;
while(q--) {
int l, r; cin>>l>>r;
cout<<T.query(l, r)<<"\n";
}
return 0;
}
