/in/foo.cc: In function 'int main()':
/in/foo.cc:20:13: error: 'LONG_MAX' was not declared in this scope
  b[n + 1] = LONG_MAX;
             ^~~~~~~~
/in/foo.cc:20:13: note: suggested alternative: 'RAND_MAX'
  b[n + 1] = LONG_MAX;
             ^~~~~~~~
             RAND_MAX