foo.cc: In function 'int main()':
foo.cc:11:2: error: 'sort' was not declared in this scope; did you mean 'qsort'?
   11 |  sort(a,a+n);
      |  ^~~~
      |  qsort
foo.cc:14:14: error: expected ';' before 'printf'
   14 |  else(n%2==0)
      |              ^
      |              ;
   15 |   printf("%.2lf",a[n/2]/a[n/2+1]*1.0);
      |   ~~~~~~      

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