foo.cc: In function 'int main()':
foo.cc:6:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |    scanf("%d",&n);
      |    ~~~~~^~~~~~~~~
foo.cc:7:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |    for(int i=0;i<n;i++) scanf("%d",&a[i]);
      |                         ~~~~~^~~~~~~~~~~~

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