a,*b=open(0) p={} def f(x): if x!=p.get(x,x):p[x]=x=f(p[x]) return x for s in b: q,a,b=map(f,s.split()) if'0'<q:print('YNEOS'[a!=b::2]) else:p[b]=a
Note that non-ascii characters in the above source code will be escaped (such as \x9f).
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