The first line of input contains an integer ‘T’ denoting the number of test cases.
The next ‘2T’ lines represent the ‘T’ test cases.
The first line of each test case contains one integers ‘N’ denoting the number of strings.
The second line contains N space-separated strings.
For each test case print the lexicographically biggest string.
1 <= T <= 50
1 <= N <= 100
1 <= length of string(si) <= 100 for all 1 <= i < = n
Time Limit: 1sec
Divisible Substrings
Ninja and Numbers
Longest Palindromic Substring
Cakes
1-3 Palindrome