#include<bits/stdc++.h>
using namespace std;
int func(string s1,string s2)
{
int k=0;
int ans=0;
string ss=s2;
for(int i=0;i<s1.size();i++)
{
int temp=0;
for(int j=0;j<min(s1.size(),ss.size());j++)
{
if(s1[j]==ss[j])
temp++;
}
ss='x'+ss;
//cout<<temp<<"\n";
ans=max(ans,temp);
}
ss=s1;
for(int i=0;i<s2.size();i++)
{
int temp=0;
for(int j=0;j<min(s1.size(),ss.size());j++)
{
if(s2[j]==ss[j])
temp++;
}
ss='x'+ss;
//cout<<temp;
ans=max(ans,temp);
}
return ans;
}
int main()
{
int t;
scanf("%d",&t);
int j=0;
while(t--)
{
int n;
scanf("%d",&n);
string s[100];
char a[100];
if(j!=0)
printf("\n");
for(int i=0;i<n;i++)
{
scanf("%s",a);
s[i]=a;
}
int ans=0;
for(int i=0;i<n;i++)
{
for(int j=i+1;j<n;j++)
{
ans=max(ans,func(s[i],s[j]));
}
}
printf("%d",ans);
j++;
}
return 0;
}
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