foo.cc: In function 'int main()':
foo.cc:39:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   39 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
foo.cc:41:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   41 |   scanf("%d", &a[i]);
      |   ~~~~~^~~~~~~~~~~~~
foo.cc:43:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   43 |  scanf("%d", &m);
      |  ~~~~~^~~~~~~~~~
foo.cc:46:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   46 |   scanf("%d%d", &l, &r),
      |   ~~~~~^~~~~~~~~~~~~~~~

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