foo.cc: In function 'int main()':
foo.cc:105:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  105 |         scanf("%d",&N);
      |         ~~~~~^~~~~~~~~
foo.cc:109:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  109 |                 scanf("%d",&tmp);
      |                 ~~~~~^~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务