foo.cc: In function 'int main()':
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:9:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  for(int i=2;i<=n;i++) scanf("%d",&f[i]);
      |                        ~~~~~^~~~~~~~~~~~
foo.cc:10:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |  for(int i=1;i<=n;i++) scanf("%d",&c[i]);
      |                        ~~~~~^~~~~~~~~~~~

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