/in/foo.cc: In function 'int main()':
/in/foo.cc:26:17: error: expected ',' or ';' before 'for'
   26 |                 for (int j=2;j*j<=b[i];j++)
      |                 ^~~
/in/foo.cc:26:30: error: 'j' was not declared in this scope
   26 |                 for (int j=2;j*j<=b[i];j++)
      |                              ^