foo.cc: In function 'int main()':
foo.cc:13:73: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   13 |                 if((a*i*i*i+b*i*i+c*i+d)==0||(a*i*i*i+b*i*i+c*i+d)<=0.01&&(a*i*i*i+b*i*i+c*i+d)>=-0.01)
      |                                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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