foo.cc: In function 'int main(int, char**)':
foo.cc:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d %d",&n1,&n2);
      |  ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:10:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%d",&arr1[i]);
      |   ~~~~~^~~~~~~~~~~~~~~
foo.cc:14:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |   scanf("%d",&arr2[i]);
      |   ~~~~~^~~~~~~~~~~~~~~

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