foo.cc: In function 'int main()':
foo.cc:8:2: warning: value computed is not used [-Wunused-value]
    8 |  int (k=a/b);
      |  ^~~~~~~~~~~
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%lf%lf",&a,&b);
      |  ~~~~~^~~~~~~~~~~~~~~~

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