foo.c: In function 'main':
foo.c:8:13: warning: comparison between pointer and integer
    8 |         if(c=="+")
      |             ^~
foo.c:8:13: warning: comparison with string literal results in unspecified behavior [-Waddress]
foo.c:10:13: warning: comparison between pointer and integer
   10 |         if(c=="-")
      |             ^~
foo.c:10:13: warning: comparison with string literal results in unspecified behavior [-Waddress]

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