// 01001100 01001111 01010100 01000001 \\
// \\
// ╦ ╔═╗╔╦╗╔═╗ \\
// ║ ║ ║ ║ ╠═╣ \\
// ╩═╝╚═╝ ╩ ╩ ╩ \\
// \\
// 01001100 01001111 01010100 01000001 \\
#include <bits/stdc++.h>
using namespace std;
#define N 500001
#define nl '\n'
#define ff first
#define ss second
#define ll long long
#define ld long double
#define terminator main
#define pll pair<ll,ll>
#define append push_back
#define pii pair<int,int>
#define all(x) (x).begin(),(x).end()
#define L0TA ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)
int a[N];
bool vis[N];
void solve(){
string s;
int n, q, l, r, o, x;
cin >> n >> s;
for(int i = 0; i < n; i++){
if(s[i] == 'C') a[i + 1] = 1;
else a[i + 1] = - 1;
}
cin >> q;
while(q--){
cin >> l >> r;
o = x = 0;
for(int i = l; i <= r; i++){
if(a[i] + o < 0){
vis[i] = 1;
x++;
}
else o += a[i];
}
o = 0;
for(int i = r; i >= l; i--){
if(vis[i]) vis[i] = 0;
else if(a[i] + o < 0) x++;
else o += a[i];
}
cout << x << nl;
}
}
int terminator(){
L0TA;
solve();
return 0;
}
