#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	int N, W;
	cin >> N >> W;
	vector<int> A(N);
	REP(i, N) scanf("%d", &A[i]);
	auto compress = [](auto &&v, auto &&cv) -> void {
		for (auto &&u : v) cv.emplace_back(u);
		std::sort(std::begin(cv), std::end(cv));
		cv.erase(std::unique(std::begin(cv), std::end(cv)), std::end(cv));
		for (auto &&u : v) u = std::lower_bound(std::begin(cv), std::end(cv), u) - std::begin(cv);
	};
	vector<int> cx;
	compress(A, cx);
	
	int ans = 0;
	int r = 0, sum = 0;
	vector<bool> done(cx.size());
	REP(i, N) {
		chmax(r, i);
		while (r < N && sum + cx[A[r]] <= W && !done[A[r]]) {
			sum += cx[A[r]];
			done[A[r++]] = true;
		}
		chmax(ans, r - i);
		
		if (r > i) {
			sum -= cx[A[i]];
			done[A[i]] = false;
		}
	}
	cout << ans << endl;
}