foo.cc: In function 'int main()':
foo.cc:13:86: warning: comparison of integer expressions of different signedness: 'unsigned int' and 'int' [-Wsign-compare]
   13 |         if(a % abs(b) == 0 && ((a < 0 && b > 0) || (a > 0 && b < 0)) || (a == 0 && a == b))
      |                                                                                    ~~^~~~
foo.cc:13:28: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   13 |         if(a % abs(b) == 0 && ((a < 0 && b > 0) || (a > 0 && b < 0)) || (a == 0 && a == b))
      |            ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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