foo.cc: In function 'int main()':
foo.cc:27:14: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |   newp->next = p;
      |   ~~~~~~~~~~~^~~
foo.cc:69:11: note: 'ans' was declared here
   69 |  PolyList ans(a, b, n);
      |           ^~~

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