foo.cc: In function 'int main()':
foo.cc:6:5: error: 'prime' was not declared in this scope
  if(prime(n))
     ^~~~~
foo.cc:6:5: note: suggested alternative: 'stime'
  if(prime(n))
     ^~~~~
     stime
foo.cc:10:17: error: 'sqrt' was not declared in this scope
  for(int i=2;i<=sqrt(n);i++)
                 ^~~~
foo.cc:10:17: note: suggested alternative: 'qsort'
  for(int i=2;i<=sqrt(n);i++)
                 ^~~~
                 qsort
foo.cc:12:16: error: 'prime' was not declared in this scope
   if(n%i==0 && prime(i) && prime(n/i))
                ^~~~~
foo.cc:12:16: note: suggested alternative: 'stime'
   if(n%i==0 && prime(i) && prime(n/i))
                ^~~~~
                stime

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