参考答案：

#include<iostream>
#include <cctype>
#include<string>
#include<algorithm>
using namespace std;
string a;
int main()
{
    int t;
    cin >> t;
    int sum = 0;
    while (t--)
    {
        int n;
        cin >> n;
        for (int i = 0; i < n; ++i)
        {
            cin >> a;
            if (a[0] == 'b' && a[1] == 'n' && a[2] == 'u' && a[3] == '1' && a[4] == '6')
            {
                ++sum;
            }
        }
        cout << sum << endl;
        sum = 0;
    }
    return 0;
}