foo.cc: In function 'int main()':
foo.cc:23:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |  int n,a,b;scanf("%d", &n);scanf("%d", &a);
      |            ~~~~~^~~~~~~~~~
foo.cc:23:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |  int n,a,b;scanf("%d", &n);scanf("%d", &a);
      |                            ~~~~~^~~~~~~~~~

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