Professor John
Time Limit: 1 Second Memory Limit: 32768 KB
Sunny Cup 2003 - Preliminary Round
April 20th, 12:00 - 17:00
Problem H: Professor John
Professor John is investigating a math problem. He has obtained some relations
among several variables. Now he would like to know if there are any other relations
that can be deduced from these obtained ones. Since he has been working for
too long, Professor John decides to grant himself a vacation while assigning
you to do the job. Are you ready?
Input
The first line of input contains an integer N, which is the number of test
cases. Then N test cases follow.
For each test case:
the 1st line contains a positive integer m (<= 100) which is the number of
given relations;
the following m lines each contains a given relation, in the format
Variable1
or
Variable1>Variable2
A "Variable" is represented by a capital character. There will not be conflicting relations given.
Output
For each test case, first print in one line "Case d:" where d is
the number of the test case, start counting from 1.
Then output all the relations which can be deduced from the given relations
in alphabetical order, in the format Variable1
If no new relation is found, output "NONE" in one line.
Sample Input
2 3 A C>B C 2 A C
Sample Output
Case 1: A A B Case 2: NONESubmit
Source: Zhejiang University Local Contest 2003, Preliminary