You are given a series of equations of the form or . (Where and represent some variable). You are tasking with finding out whether each equation is consistent with the previous equations. If the equation is inconsistent, you may assume it is false for the following equations.
Input
The first line contains an integer , stating the number of equations.
The following lines are of the form a b c
, stating where a
and b
are strings.
Output
For each equation, output a line containing Yes
or No
, stating whether it is consistent with the previous equations.
Example 1
Input
10
c c -1
a b 1
c c 1
d e 1
c e 1
c a 1
b e -1
b b -1
b b -1
e b 1
Output
No
Yes
Yes
Yes
Yes
Yes
No
No
No
Yes
Example 2
Input
20
c b 1
e c -1
b b 1
d f -1
a d -1
b c 1
d b 1
f e -1
d b 1
e d 1
c d 1
f a -1
e e 1
c b 1
d d 1
d e -1
b a 1
b a 1
d f 1
a f -1
Output
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
Yes
No
Yes
Yes
Yes
Yes
No
No
No
No
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