/in/foo.c: In function 'main':
/in/foo.c:19:5: error: 'cout' undeclared (first use in this function)
   19 |     cout<<"%d\n",maxQ<<endl;
      |     ^~~~
/in/foo.c:19:5: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:19:24: error: 'endl' undeclared (first use in this function)
   19 |     cout<<"%d\n",maxQ<<endl;
      |                        ^~~~
/in/foo.c:19:17: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   19 |     cout<<"%d\n",maxQ<<endl;
      |                 ^