foo.cc: In function 'void init()':
foo.cc:14:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~
foo.cc:17:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |         scanf("%d", &x);
      |         ~~~~~^~~~~~~~~~
foo.cc:18:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |         scanf("%d%d", &w[x], &num[x]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:21:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |             scanf("%d", &y);
      |             ~~~~~^~~~~~~~~~

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