foo.c: In function 'main':
foo.c:7:10: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
  scanf("%d",n);
         ~^
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",n);
  ^~~~~~~~~~~~~
foo.c:7:2: warning: 'n' is used uninitialized in this function [-Wuninitialized]
  scanf("%d",n);
  ^~~~~~~~~~~~~

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