foo.cc: In function 'int main()':
foo.cc:28:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   28 |         scanf("%d",&n);
      |         ~~~~~^~~~~~~~~
foo.cc:29:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   29 |         for(int i = 1;i <= n;i++) scanf("%d",a+i);
      |                                   ~~~~~^~~~~~~~~~
foo.cc:30:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |         scanf("%d",&m);
      |         ~~~~~^~~~~~~~~
foo.cc:31:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |         for(int i = 1;i <= m;i++) scanf("%d",b+i);
      |                                   ~~~~~^~~~~~~~~~

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