/in/foo.c: In function 'num':
/in/foo.c:5:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Wformat=]
    5 |         printf("%d",n%2);
      |                 ~^  ~~~
      |                  |   |
      |                  int long int
      |                 %ld
/in/foo.c:2:6: warning: infinite recursion detected [-Winfinite-recursion]
    2 | void num(long int n)
      |      ^~~
/in/foo.c:4:9: note: recursive call
    4 |         num(n / 2);
      |         ^~~~~~~~~~