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SPOJ Problem Set (classical)

4033. Phone List

Problem code: PHONELST

Phone List Given a list of phone numbers, determine if it is consistent in the sense that no number is the prefix of another. Let’s say the phone catalogue listed these numbers:

• Emergency 911

• Alice 97 625 999

• Bob 91 12 54 26

In this case, it’s not possible to call Bob, because the central would direct your call to the emergency line as soon as you had dialled the first three digits of Bob’s phone number. So this list would not be consistent.

Input

The first line of input gives a single integer, 1 <= t <= 40, the number of test cases. Each test case starts with n, the number of phone numbers, on a separate line, 1 <= n <= 10000. Then follows n lines with one unique phone number on each line. A phone number is a sequence of at most ten digits.

Output

For each test case, output “YES” if the list is consistent, or “NO” otherwise.

Example

Input:
2
3
911
97625999
91125426
5
113
12340
123440
12345
98346

Output:
NO
YES

Added by:Andres Galvis
Date:2009-03-08
Time limit:1s-3s
Source limit:50000B
Memory limit:256MB
Cluster: Pyramid (Intel Pentium III 733 MHz)
Languages:All except: ERL JS NODEJS PERL 6
Resource:Nordic Collegiate Programming Contest 2007

hide comments
2014-12-18 11:58:11 Vamsi Krishna Avula
simple sort would do it :)
2014-12-04 07:59:30 DanFT [ICMC - USP]
was gettin TLE, switched from cin,cout to scanf, printf got AC
2014-12-04 00:17:23 surayans tiwari(http://bit.ly/1EPzcpv)
can be done by a simple sort
2014-12-02 14:35:23 Rajat (1307086)
@mohannad abdullah hassan yes
T.L.E wih ternary search trees.Why??

Last edit: 2014-12-02 14:36:02
2014-11-24 15:06:20 mayank
Simple! :)
2014-09-28 20:46:27 Stannis Baratheon
Downloaded the sample testcases from the <Resource> & compared my output against the correct output; it matches. But WA here. Strange.
2014-07-24 14:07:24 Archit Jain
nice question
2010-06-19 11:54:12 Mohannad Abdullah Hassan
Can any number start with a zero?
2009-07-23 07:22:21 vaibhav paliwal
no
2009-06-29 22:34:28 madhav
are there any spaces b/w the digits of the phone number??
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