foo.cc: In function 'int main()':
foo.cc:12:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&l,&m);
  ~~~~~^~~~~~~~~~~~~~~
foo.cc:16:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d",&s[i],&t[i]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~

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