#include "bits/stdc++.h"
using namespace std;
#define int long long
#define REP(i, n) for (int i = 0; i < (int)n; ++i)
#define RREP(i, n) for (int i = (int)n - 1; i >= 0; --i)
#define FOR(i, s, n) for (int i = s; i < (int)n; ++i)
#define RFOR(i, s, n) for (int i = (int)n - 1; i >= s; --i)
#define ALL(a) a.begin(), a.end()
#define IN(a, x, b) (a <= x && x < b)
template<class T>istream&operator >>(istream&is,vector<T>&vec){for(T&x:vec)is>>x;return is;}
template<class T>inline void out(T t){cout << t << "\n";}
template<class T,class... Ts>inline void out(T t,Ts... ts){cout << t << " ";out(ts...);}
template<class T>inline bool CHMIN(T&a,T b){if(a > b){a = b;return true;}return false;}
template<class T>inline bool CHMAX(T&a,T b){if(a < b){a = b;return true;}return false;}
constexpr int INF = 1e18;



vector<int>mp(string s) {
	vector<int>ret(s.size() + 1);
	ret[0] = -1;
	int j = -1;
	for(int i = 0; i < s.size(); i++) {
		while(j >= 0 && s[i] != s[j]) j = ret[j];
		++j;
		ret[i + 1] = j;
	}
	return ret;
}

signed main(){
	int N, W;
	cin >> N >> W;
	vector<int>a(N);
	cin >> a;
	int r = 0, sum = 0, ans = 0;
	set<int>st;
	for(int l = 0; l < N; l++) {
		while(r < N && sum + a[r] < W && st.find(a[r]) == st.end()) {
			st.insert(a[r]);
			sum += a[r];
			++r;
		}
		CHMAX(ans, r - l);
		if(l == r) {
			++r;
		} else {
			sum -= a[l];
			st.erase(a[l]);
		}
	}
	out(ans);
}