#include <bits/stdc++.h>
using namespace std;

struct iofast_t {
    iofast_t() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
    }
} iofast;

struct uns_t {} uns;
template <typename Element, typename Head, typename ...Args>
auto vec(Element init, Head arg, Args ...args) {
    if constexpr (sizeof...(Args) == 0) return vector(arg, init);
    else return vector(arg, vec(init, args...));
}
template <typename Element, typename Head, typename ...Args>
auto vec(uns_t, Head arg, Args ...args) {
    return vec(Element(), arg, args...);
}

template <typename Container>
auto distance(const Container &c, decltype(begin(c)) iter) {
    return distance(begin(c), iter);
}

template <typename RIter, typename Compare = less<typename iterator_traits<RIter>::value_type>>
auto isort(RIter first, RIter last, Compare comp = Compare()) {
    vector<int> i(distance(first, last));
    iota(begin(i), end(i), 0);
    sort(begin(i), end(i), [&](auto x, auto y) {
        return comp(*(first + x), *(first + y));
    });
    return i;
}

template <typename, template <typename> typename, typename = void_t<>>
struct detect : false_type {};
template <typename T, template <typename> typename Check>
struct detect<T, Check, void_t<Check<T>>> : true_type {};
template <typename T, template <typename> typename Check>
constexpr inline bool detect_v = detect<T, Check>::value;

template <typename T>
using has_member_sort = decltype(declval<T>().sort());

template <typename Container, typename Compare = less<typename Container::value_type>>
auto sorted(Container c, Compare comp = Compare()) {
    if constexpr (detect_v<Container, has_member_sort>) {
        c.sort(comp);
        return c;
    }
    else {
        sort(begin(c), end(c), comp);
        return c;
    }
}

template <typename Container, typename Compare = equal_to<typename Container::value_type>>
auto uniqued(Container c, Compare comp = Compare()) {
    c.erase(unique(begin(c), end(c), comp), end(c));
    return c;
}

template <typename T, typename Compare = less<T>>
T &chmin(T &l, T r, Compare &&f = less<T>()) { return l = min(l, r, f); }
template <typename T, typename Compare = less<T>>
T &chmax(T &l, T r, Compare &&f = less<T>()) { return l = max(l, r, f); }

template <typename F>
constexpr auto fix(F &&f) noexcept {
    return [f = std::tuple<F>(std::forward<F>(f))](auto &&...args) mutable {
        return std::get<0>(f)(fix(std::get<0>(f)), std::forward<decltype(args)>(args)...);
    };
}

#include <atcoder/segtree>

constexpr auto inf = INT_MAX / 4;

int op(int x, int y) {
    return min(x, y);
}
int elem() {
    return inf;
}

using segtree = atcoder::segtree<int, op, elem>;

int main() {
    int n, w; cin >> n >> w;
    auto a = vec<int>(uns, n);
    for (auto &e : a) cin >> e;

    auto acc = vec<int64_t>(uns, n + 1);

    acc[0] = 0;
    for (int i = 0; i < n; ++i) {
        acc[i + 1] = acc[i] + a[i];
    }

    segtree seg([&]() {
        map<int, optional<int>> last;

        auto r = vec<int>(uns, n);
        for (int i = n - 1; 0 <= i; --i) {
            r[i] = last[a[i]].value_or(n); last[a[i]] = i;
        }

        return r;
    }());

    auto check = [&](int m) {
        for (int i = 0; i + m <= n; ++i) {
            if (w < acc[i + m] - acc[i]) {
                continue;
            }
            if (seg.prod(i, i + m) < i + m) {
                continue;
            }
            return true;
        }
        return false;
    };

    int l = 0, r = n + 1;
    while (1 < r - l) {
        int m = l + (r - l) / 2;

        if (check(m)) {
            l = m;
        }
        else {
            r = m;
        }
    }

    cout << l << endl;
}