foo.c: In function 'main':
foo.c:8:14: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'long int *' [-Wformat=]
      scanf("%d",&x[k]);
             ~^  ~~~~~
             %ld
foo.c:27:12: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Wformat=]
   printf("%d\n",b);
           ~^
           %ld
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:8:6: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
      scanf("%d",&x[k]);
      ^~~~~~~~~~~~~~~~~

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