#ifndef LOCAL
#define NDEBUG 1
#endif // LOCAL
#include<bits/stdc++.h>
const int max_n=500000;
int n;
std::string str;
struct Node {
int max_l, max_r, tot, ans;
Node operator + (Node const& other) {
Node ret;
ret.max_l=std::max(max_l, tot+other.max_l);
ret.max_r=std::max(max_r+other.tot, other.max_r);
ret.tot=tot+other.tot;
ret.ans=std::max(std::max(ans+other.tot, tot+other.ans), max_l+other.max_r);
return ret;
}
};
Node nodes[max_n<<2];
int L[max_n<<2], H[max_n<<2];
void build(int node, int low, int high) {
L[node]=low;
H[node]=high;
if (low==high) {
if (str[high-1]=='C') {
nodes[node]={0, 0, -1, 0};
}
else {
nodes[node]={1, 1, 1, 1};
}
return ;
}
int mid=low+high>>1;
build(node<<1, low, mid);
build(node<<1|1, mid+1, high);
nodes[node]=nodes[node<<1]+nodes[node<<1|1];
}
Node get(int node, int leftq, int rightq) {
if (L[node]>rightq or H[node]<leftq) {
return {0, 0, 0, 0};
}
if (L[node]>=leftq and H[node]<=rightq) {
return nodes[node];
}
return get(node<<1, leftq, rightq)+get(node<<1|1, leftq, rightq);
}
int main() {
std::ios_base::sync_with_stdio(0); std::cin.tie(0);
int q;
std::cin>>n>>str>>q;
build(1, 1, n);
while (q--) {
int x, y; std::cin>>x>>y;
std::cout<<get(1, x, y).ans<<"\n";
}
return 0;
}
