/in/foo.cc:3:13: error: 'MAX_NUM' was not declared in this scope; did you mean 'MAX_INPUT'?
    3 | const int N=MAX_NUM;
      |             ^~~~~~~
      |             MAX_INPUT
/in/foo.cc:4:7: error: size of array 'a' is not an integral constant-expression
    4 | int a[N];
      |       ^