foo.cc: In function 'int main()':
foo.cc:13:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |     scanf("%d %d",&n,&a[1]);
      |     ~~~~~^~~~~~~~~~~~~~~~~~
foo.cc:16:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |   scanf("%d",&a[i]);
      |   ~~~~~^~~~~~~~~~~~
foo.cc:12:12: warning: 'n' is used uninitialized in this function [-Wuninitialized]
   12 |     int a[n];
      |            ^

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