B.cpp

#include<bits/stdc++.h>
using namespace std;
#define loi long long
#define lod long double
#define doubel double
#define pb push_back
#define run ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define mod 1000000007
#define lim 5000000000000000000
#define in(ar, n) for(loi i = 0; i < n; i++) cin >> ar[i];
#define out(ar, n) for (loi i = 0; i < n; i++) cout << ar[i] << " "; cout << "\n";
#define rep(i, n) for(loi i = 0; i < n; i++)
#define rep1(i, n) for(loi i = 1; i <= n; i++)
#define rev(i, n) for(loi i = n - 1; ~i; i--)
#define rep3(i, l, r) for(loi i = l; i <= r; i++)
#define rev3(i, r, l) for(loi i = r; i >= l; i--)
#define rep4(i, r, l) for(loi i = r; i >= l; i--)
#define all(x) x.begin(), x.end ()
#define mkp make_pair
#define vii vector<loi>
#define mii map<loi, loi>
#define sii set<loi>
#define pii pair<loi, loi>
#define mxdepth 23 // FOR LCA til N = 1e6
#define mxn 2000001

int main()
{
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    
    run;
    int t;
    cin >> t;

    for(loi tc = 1; tc <= t; tc++)
    {
        loi n;
        cin >> n;
        string s;
        cin >> s;

        loi cnta = 0, cntb = 0;

        rep(i, n)
        {
            if(s[i] == 'A') cnta++;
            else cntb++;
        }

        cnta -= cntb;
        cnta = abs(cnta);

        cout << "Case #" << tc << ": ";

        if(cnta == 1)
         cout << "Y\n";
        
        else cout << "N\n";
    }

    return 0;
}