foo.c: In function 'main':
foo.c:48:16: warning: 'n2' may be used uninitialized [-Wmaybe-uninitialized]
   48 |         c = n2 - n1 + day2 - day1 ;
      |             ~~~^~~~
foo.c:29:13: note: 'n2' was declared here
   29 |         int n2;
      |             ^~
foo.c:48:16: warning: 'n1' may be used uninitialized [-Wmaybe-uninitialized]
   48 |         c = n2 - n1 + day2 - day1 ;
      |             ~~~^~~~
foo.c:11:13: note: 'n1' was declared here
   11 |         int n1;
      |             ^~

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