foo.cc: In function 'int main()':
foo.cc:16:9: warning: 're' may be used uninitialized in this function [-Wmaybe-uninitialized]
   16 |  cout<< n <<endl;
      |         ^
foo.cc: In function 'int f(int*)':
foo.cc:31:9: warning: 're' may be used uninitialized in this function [-Wmaybe-uninitialized]
   31 |  return re;
      |         ^~

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