foo.cc: In function 'int main()':
foo.cc:31:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:32:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |  scanf("%d%d",&m1,&m2);
      |  ~~~~~^~~~~~~~~~~~~~~~
foo.cc:36:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   36 |   scanf("%lld",&now);
      |   ~~~~~^~~~~~~~~~~~~

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