foo.cc: In function 'int max(Node*)':
foo.cc:29:14: warning: statement has no effect [-Wunused-value]
   29 |         for (p; p != NULL; p = p->next)
      |              ^
foo.cc:37:14: warning: statement has no effect [-Wunused-value]
   37 |         for (p; p != NULL; p = p->next)
      |              ^
foo.cc:42:16: warning: 'm' may be used uninitialized [-Wmaybe-uninitialized]
   42 |         return m;
      |                ^
foo.cc:28:13: note: 'm' was declared here
   28 |         int m;
      |             ^

[Hydro](https://hydro.ac)提供评测服务