#include<iostream>
#include<math.h>
using namespace std;
int main()
{
    int a,s;
	cout<<"enter a decimal no";
	int b;
	cin>>b;
	int c,d,e[100],count=0,i=0;
	while(b!=1)
	{
 			c=b%2;
			b=b/2;
			e[i]=c;
			count++;
			i++;	
    }
    e[i]=1;
    
	int j;
	for(j=count;j>=0;j--)
	{
		cout<<e[j];
		  }  
		

}
