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<pre name="code" class="delphi">var  f:array[0..5001] of longint;  i,n,m,p,x,y:longint;function find(x:longint):longint;begin  if f[x]=x then exit(x);  f[x]:=find(f[x]);  exit(f[x]);end;begin  readln(n,m,p);  for i:=1 to n do    f[i]:=i;  for i:=1 to m do  begin    readln(x,y);    f[find(x)]:=find(y);  end;  for i:=1 to p do  begin    readln(x,y);    if (find(x)=find(y)) then writeln('Yes')      else writeln('No');  end;end.