#include<bits/stdc++.h>
using namespace std;
#define reg register
typedef long long ll;
#define rep(i,a,b) for(int i=a,i##end=b;i<=i##end;++i)
#define drep(i,a,b) for(int i=a,i##end=b;i>=i##end;--i)
typedef pair <int,int> Pii;
typedef unsigned long long ull;
typedef double db;
#define mp make_pair
#define pb push_back
#define Mod1(x) ((x>=P)&&(x-=P))
#define Mod2(x) ((x<0)&&(x+=P))
template <class T> inline void cmin(T &a,T b){ ((a>b)&&(a=b)); }
template <class T> inline void cmax(T &a,T b){ ((a<b)&&(a=b)); }

char IO;
template <class T=int> T rd(){
    T s=0; int f=0;
    while(!isdigit(IO=getchar())) if(IO=='-') f=1;
    do s=(s<<1)+(s<<3)+(IO^'0');
    while(isdigit(IO=getchar()));
    return f?-s:s;
}
const int N=1e5+10;

int n;
char s[N];
int cnt[10];
int dp[6][1<<10];




int main(){
    rep(kase,1,rd()) {
        n=rd();
        memset(cnt,0,sizeof cnt);
        rep(i,1,n) {
            scanf("%s",s);
            cnt[s[strlen(s)-1]-'0']++;
        }
        memset(dp,-63,sizeof dp);
        dp[0][0]=1e9;
        rep(i,1,5) {
            rep(S,0,(1<<10)-1) if(dp[i-1][S]>=0) {
                rep(T,0,(1<<10)-1) if((S&T)==0) {
                    int s=0;
                    rep(j,0,9) if(T&(1<<j)) s+=cnt[j];
                    cmax(dp[i][S|T],min(dp[i-1][S],s));
                }
            }
        }
        int ma=0;
        rep(i,0,(1<<10)-1) cmax(ma,dp[5][i]);
        printf("%d\n",n-ma);
    }
}