foo.cc: In function 'int main()':
foo.cc:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
foo.cc:14:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |   scanf("%d", &x);
      |   ~~~~~^~~~~~~~~~
foo.cc:20:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |    scanf("%d", &x);
      |    ~~~~~^~~~~~~~~~

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