foo.cc: In function 'int main()':
foo.cc:42:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   42 |  scanf("%d%d%d",&n,&j,&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%d",&a,&b,&c);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~

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