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#include <iostream>
using namespace std;
int main()
{
 int year;
 bool leap;
 cout<<"please enter year";
 cin>>year;
 if(year%4==0)
 {if(year%100==0)
 if(year%400==0)
  leap=true;
 else
  leap=false;
 }
 else
  leap=true;
}
else leap=false;
if(leap)
cout<<year<<"is";
else
cout<<year<<"is not";
cout<<"a leap year."<<endl;
return 0;
}