foo.c: In function 'main':
foo.c:12:11: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Wformat=]
  printf("%d\n", x);
          ~^
          %ld
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%ld", &n);
  ^~~~~~~~~~~~~~~~

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