foo.cc: In function 'int search(int)':
foo.cc:18:1: warning: control reaches end of non-void function [-Wreturn-type]
   18 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:21:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:22:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   22 |  for(int i=1;i<=n;i++)scanf("%d",a+i);
      |                       ~~~~~^~~~~~~~~~
foo.cc:24:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |  scanf("%d",&x);
      |  ~~~~~^~~~~~~~~

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