문제<\/h2>
The judges of NWRRC came up with $n<\/mi><\/mrow>n<\/math><\/span><\/span> n<\/span><\/span><\/span><\/span> problems on a similar topic and decided to use them for n<\/mi><\/mrow>n<\/math><\/span><\/span> n<\/span><\/span><\/span><\/span> consecutive years, one problem per year. The only question was: in what order should they be used?<\/p> Each problem's name consists of two words. Let's call two names similar<\/em> if either their first words are the same or their second words are the same. For example, eight shaped<\/code> and eight connected<\/code> are similar, while hello world<\/code> and world hello<\/code> are not.<\/p> The judges decided to implement the following rule: in the first year, they chose a problem arbitrarily. In every subsequent year, if there was a problem with a name similar to the previous year's problem that was still unused, they chose one of such problems; otherwise, they chose any unused problem.<\/p> You are given the names of the problems in chronological order of their use. Determine whether the judges correctly followed the rule above, or if they made a mistake.<\/p> 입력<\/h2> Each test contains multiple test cases. The first line contains the number of test cases t<\/mi><\/mrow>t<\/math><\/span><\/span> t<\/span><\/span><\/span><\/span> (1<\/mn>\leq<\/mo>t<\/mi>\leq<\/mo>10<\/mn>4<\/mn><\/msup><\/mrow>1 \le t \le 10^4<\/math><\/span><\/span> 1<\/span> <\/span> \leq<\/span> <\/span><\/span> <\/span>$

Judging Problem