#include <bits/stdc++.h>
#define pb push_back
#define tree int h,int l,int r
#define left (h<<1),l,(l+r)>>1
#define right ((h<<1)|1),((l+r)>>1) + 1,r
using namespace std;
const int N = 200005;
string s;
struct {
int l = 0; // max prefix sum
int r = 0; // max suffix sum
int s = 0;
int ans = 0;
} t[4*N];
void UPDnode(int h){
t[h].s = t[h*2].s + t[h*2 + 1].s;
t[h].l = max(t[h*2].l,t[h*2].s + t[h*2 + 1].l);
t[h].r = max(t[h*2 + 1].r,t[h*2].r + t[h*2+1].s);
t[h].ans = max({t[h*2].ans + t[h*2+1].s,t[h*2+1].ans + t[h*2].s,t[h*2].l + t[h*2 + 1].r});
}
void U(int h,int l){
if (s[l] == 'C') {
t[h].ans = t[h].l = 0,t[h].r = 0;
t[h].s = -1;
}else{
t[h].s = t[h].ans = t[h].l = t[h].r = 1;
}
}
void build(tree){
if (l == r){
U(h,l);
return;
}
build(left);
build(right);
UPDnode(h);
}
vector <int> get(tree,int L,int R){
if (r < L || R < l) return {0,0,0,0};
if (L <= l && r <= R) return {t[h].l,t[h].r,t[h].s,t[h].ans};
vector <int> x = get(left,L,R),y = get(right,L,R),z = {0,0,0,0};
z[2] = x[2] + y[2];
z[0] = max(x[0],x[2] + y[0]);
z[1] = max(y[1],x[1] + y[2]);
z[3] = max({x[3] + y[2],y[3] + x[2],x[0] + y[1]});
return z;
}
main (){
ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
int n;
cin>>n;
cin>>s;
s='%' + s;
build(1,1,n);
int m;
cin>>m;
for (int i = 1; i <= m; i++){
int l,r;
cin>>l>>r;
vector <int> res = get(1,1,n,l,r);
cout<<res[3]<<"\n";
}
}
