foo.cc: In function 'int main()':
foo.cc:18:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
foo.cc:20:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ~~~~~^~~~~~~~~~~~
foo.cc:22:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&k);
  ~~~~~^~~~~~~~~
foo.cc: In function 'void Insert(int*, int, int)':
foo.cc:11:5: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  a[y]=x;
     ^
foo.cc: In function 'int main()':
foo.cc:11:5: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  a[y]=x;
     ^
foo.cc:5:6: note: 'y' was declared here
  int y;
      ^

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