玄关求条，90分

#include <bits/stdc++.h>
using namespace std;
unsigned long long k,n;
unsigned long long dfs (unsigned long long x,unsigned long long y)
{
	if(x==1ull) 
	{
		if(y==1ull) return 0ull;
		else return 1ull;
	}
	if(y<=(1ull<<(x-1)))
    	return dfs(x-1,y);
    else
        return dfs(x-1,(1ull<<x)-y+1)+(1ull<<(x-1ull));
}
int main()
{
	cin>>n>>k;
    unsigned long long cnt=0,p;
	bool ans[100001]; 
	p=dfs(n,k+1ull);
	while(p>0)
	{
		ans[++cnt]=p%2ull;
		p/=2ull; 
	}
	for(int i=1;i<=n-cnt;i++) cout<<0;
	for(int i=cnt;i>=1;i--) cout<<ans[i];
	return 0;
}