foo.cc: In function 'int main()':
foo.cc:81:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   81 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:84:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   84 |   scanf("%d",&s[i]);
      |   ~~~~~^~~~~~~~~~~~
foo.cc:87:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   87 |  scanf("%d",&m);
      |  ~~~~~^~~~~~~~~
foo.cc:92:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   92 |   scanf("%d",&op);
      |   ~~~~~^~~~~~~~~~
foo.cc:95:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   95 |    scanf("%d%d%lld",&x,&y,&s);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~~
foo.cc:100:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  100 |    scanf("%d%d",&x,&y);
      |    ~~~~~^~~~~~~~~~~~~~

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