foo.cc: In function ‘int main()’:
foo.cc:10:55: error: expected ‘;’ before ‘if’
   10 |                 f[i]=sqrt(f[i-1]*f[i-1]+f[i-2]*f[i-2])
      |                                                       ^
      |                                                       ;
   11 |                 if(f[i]>e)
      |                 ~~