foo.c: In function 'main':
foo.c:7:13: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'long long int *' [-Wformat=]
  scanf("%d %d",&n,&k);
            ~^     ~~
            %lld
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&n,&k);
  ^~~~~~~~~~~~~~~~~~~~

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