#include<bits/stdc++.h>
#define Max(a,b) ((a<b)&&(a=b))
#define Min(a,b) ((a>b)&&(a=b))
#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)
#define erep(i,a) for(int i=hd[a],y;(y=to[i]);i=nxt[i])
using namespace std;
typedef long long ll;
char C;
inline int rd() {
    int res=0,f=1;
    while(C=getchar(),C<48||C>57)if(C=='-')f=0;
    do res=(res<<3)+(res<<1)+(C^48);
    while(C=getchar(),C>=48&&C<=57);
    if(f)return res;
    return -res;
}
int cnt[15],sum[1030],dp[10][1030];
int main(){
    int T=rd();
    while(T--){
        int n=rd(),s=0,ans=2e9;
        memset(cnt,0,sizeof cnt);
        memset(sum,0,sizeof sum);
        rep(i,1,n){
            int t=rd();
            cnt[t%10]++,s++;
        }
        int S=(1<<10)-1;
        rep(i,0,S)rep(j,0,9)if(1<<j&i)sum[i]+=cnt[j];
        memset(dp,63,sizeof dp);
        memset(dp[0],0,sizeof dp[0]);
        rep(i,1,5){
            rep(j,0,S)rep(k,0,S)if((j&k)==0){    
                Min(dp[i][j|k],max(dp[i-1][k],s-sum[j]));
                if(i==5)Min(ans,dp[i][j|k]);
            }
        }
        cout<<ans<<endl;
    }
}