#include <bits/stdc++.h>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int T;
    cin >> T;

    while(T--) {
        int n;
        cin >> n;

        vector<int> cnt(10);
        for(int i = 0; i < n; ++i) {
            string s;
            cin >> s;
            cnt[s.back() - '0'] += 1;
        }

        int ans = n;
        vector<int> tot(5);
        function<void(int, int)> dfs = [&] (int cur, int c) {
            if(cur == 10) {
                ans = min(ans, n - *min_element(tot.begin(), tot.end()));    
                return;    
            }

            if(c < 4) {
                tot[c + 1] += cnt[cur];
                dfs(cur + 1, c + 1);
                tot[c + 1] -= cnt[cur];
            }

            for(int i = 0; i <= c; ++i) {
                tot[i] += cnt[cur];
                dfs(cur + 1, c);
                tot[i] -= cnt[cur];
            }
        };

        dfs(0, 0);

        cout << ans << '\n';
    }

    return 0;
}