foo.cc: In function ‘bool cmp(student, student)’:
foo.cc:17:56: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
   17 |         return x.sum1()>y.sum1() || x.sum1()==y.sum1() && x.sum2()>y.sum2() || x.sum1()==y.sum1() && x.sum2()==y.sum2() && x.max1()>y.max1();
      |                                     ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:17:121: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
   17 |         return x.sum1()>y.sum1() || x.sum1()==y.sum1() && x.sum2()>y.sum2() || x.sum1()==y.sum1() && x.sum2()==y.sum2() && x.max1()>y.max1();
      |                                                                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~