foo.cc: In function 'int get_3(int, int)':
foo.cc:93:1: warning: no return statement in function returning non-void [-Wreturn-type]
   93 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:155:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  155 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
foo.cc:159:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  159 |         scanf("%d%d%d",&x,&y,&c);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~

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