foo.cc: In function 'int main()':
foo.cc:5:9: error: 'cin' was not declared in this scope
    5 |         cin>>a;
      |         ^~~
foo.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
  +++ |+#include <iostream>
    1 | using namespace std;
foo.cc:9:13: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
    9 |         if(d<c<b){
      |            ~^~
foo.cc:10:17: error: 'cout' was not declared in this scope
   10 |                 cout<<"Yes";
      |                 ^~~~
foo.cc:10:17: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
foo.cc:12:17: error: 'cout' was not declared in this scope
   12 |                 cout<<"No";
      |                 ^~~~
foo.cc:12:17: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?

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