foo.cc: In function 'int main()':
foo.cc:47:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   47 |  scanf("%d%d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~
foo.cc:48:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   48 |  for(int i=1;i<=n;i++) scanf("%d",&a[i]),id[i]=i;
      |                        ~~~~~^~~~~~~~~~~~
foo.cc:61:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   61 |   scanf("%d%d%d",&x1,&y2,&k1);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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