foo.c: In function 'main':
foo.c:7:10: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
    7 |  scanf("%d",k);
      |         ~^  ~
      |          |  |
      |          |  int
      |          int *
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d",k);
      |  ^~~~~~~~~~~~~
foo.c:7:2: warning: 'k' is used uninitialized in this function [-Wuninitialized]
    7 |  scanf("%d",k);
      |  ^~~~~~~~~~~~~
foo.c:8:2: warning: 'Sn' is used uninitialized in this function [-Wuninitialized]
    8 |  for(n=1;Sn<=k;n++){
      |  ^~~

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