Phone List#2303
Given a list of phone numbers, determine whether it is consistent, meaning it does not contain any pair of numbers where one number is a prefix of another.
Consider the following example of a phone directory:
Emergency service:
Alice:
Bob:
In this case, it is impossible to call Bob, because after dialing the first three digits of his number, you will immediately reach the emergency service. Therefore, this list is inconsistent.
The first line contains an integer t~(1 \le t \le 40) — the number of test cases.
Each test case starts with a line containing an integer n~(1 \le n \le 10^6) — the number of phone numbers.
Then follow lines, each containing a single phone number consisting of at most digits.
For each test case, print the string "YES" if the list of phone numbers is consistent, and "NO" otherwise.
Example 1