foo.cc: In function 'int main()':
foo.cc:13:6: warning: unused variable 'k' [-Wunused-variable]
   13 |  int k;
      |      ^
foo.cc:9:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf("%d %d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:11:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |  scanf("%d",&s[i]);
      |  ~~~~~^~~~~~~~~~~~

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