#include<iostream>
using namespace std;
int main()
{
    int DD,MM,YYYY;
     cout<<"Enter the DAY:"<<DD<<endl;
   // cin>>DD<<endl;
    cout<<"Enter the month:"<<endl;
    //cin>>MM<<endl;
    cout<<"Enter the year:"<<endl;
    //cin>>YYYY<<endl;
    if(1900<=YYYY>=2100,1<=MM>=12,1,=DD>=31)
    {
        cout<<YYYY"-"MM"-"DD<<endl;
    }
    else
    cout<<"invalid input"<<endl;
}