foo.cc: In function ‘int main()’:
foo.cc:10:10: warning: variable ‘p’ set but not used [-Wunused-but-set-variable]
   10 |     char p[500][500] ;
      |          ^
foo.cc:11:10: warning: unused variable ‘cube’ [-Wunused-variable]
   11 |     char cube[8][8] = {"..+---+","./   /|","+---+ |","|   | +","|   |/.","+---+..",};
      |          ^~~~