foo.c: In function 'Unique':
foo.c:33:9: warning: statement with no effect [-Wunused-value]
   33 |         for(p;p!=NULL;p=p->next)
      |         ^~~
foo.c: In function 'main':
foo.c:69:15: warning: 'head1' is used uninitialized [-Wuninitialized]
   69 |         head1=Create(head1,n1);
      |               ^~~~~~~~~~~~~~~~
foo.c:64:14: note: 'head1' was declared here
   64 |         Node*head1;
      |              ^~~~~
foo.c:70:15: warning: 'head2' is used uninitialized [-Wuninitialized]
   70 |         head2=Create(head2,n2);
      |               ^~~~~~~~~~~~~~~~
foo.c:65:14: note: 'head2' was declared here
   65 |         Node*head2;
      |              ^~~~~
foo.c:71:15: warning: 'head3' is used uninitialized [-Wuninitialized]
   71 |         head3=Create(head3,n3);
      |               ^~~~~~~~~~~~~~~~
foo.c:66:14: note: 'head3' was declared here
   66 |         Node*head3;
      |              ^~~~~

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