foo.c: In function 'main':
foo.c:28:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Wformat=]
   28 |         printf("%d", sum);
      |                 ~^   ~~~
      |                  |   |
      |                  int long int
      |                 %ld

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