#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define rep(i, l, r) for ((i) = (l); (i) <=(r); (i)++)
ll e[1000007];
ll p1[1000007];
ll p2[1000007];
ll calculate(ll x,ll y)
{
	ll s1=p1[y]-p1[x-1];
	ll k = abs(x-y)+1;
	ll s2= p2[y]-p2[x-1];
	ll sum=s2*k;
	ll answer = s1+sum;
	return answer;
}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	ll n;
	cin>>n;ll s;cin>>s;
	ll i;
	rep(i,1,n)
	{
		cin>>e[i];
		p1[i]=e[i]+p1[i-1];
		p2[i]=i+p2[i-1];
	}
	p2[n+1]=1e18;
	p1[n+1]=1e18;
	

	//cout<<"lol";
	///cout<<calculate(2,2);
	//cout<<"\n";
	ll ram=-1e18;
	rep(i,1,n)
	{
		ll low=i;
		ll high=n;
		ll answer = -1;ll km = 0 ;
	      while(low<=high && km==0)
	      {
	      	
	      	
    	            
                  ll mid=(low+high)/2;  
                   
                  if(calculate(i,mid)>s)
                  {
                   high=mid-1;    
                  }
                  else{
                  	
                  	
                   
                     
                 	
        	    
                      if(calculate(i,mid+1)<=s)
                      {
                      low=mid+1;
                      }
                      else
                      {
                      km=1;
                      answer = mid;
                      }    
                 
           
          
                 }
      
            
            
          }
		
		if(answer==-1)
		{
		
			
		}
		else
		{     ll real = abs(answer-i)+1;
		
			ram=max(ram,real);
			
		}
		
		
	
	}
	
	
	cout<<ram  ;
	
	
	
	
	
	
	
	return 0;

}