279B.cpp

#include <bits/stdc++.h>
#define mod 1000000007
#define FOR(i, a, b) for (i = a; i < b; i++)
#define FastIO                        \
    ios_base::sync_with_stdio(false); \
    cin.tie(NULL);                    \
    cout.tie(NULL);
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef priority_queue<ll, vector<ll>, greater<ll>> minheap;
typedef priority_queue<ll> maxheap;
int dxrow[] = {-1, 0, 0, 1, 1, 1, -1, -1}; //first 4 straight last 4 diagonals
int dycol[] = {0, -1, 1, 0, 1, -1, -1, 1};
void printV(vector<ll> v)
{
    for (ll i = 0; i < v.size(); i++)
        cout << v[i] << "\n";
}
ll power(ll a, ll b)
{
    return (ll)(pow(a, b) + 0.5);
}
int modexp(ll A, ll B, ll C)
{
    if (A == 0)
        return 0;
    if (B == 0)
        return 1;
    ll y;
    if (B % 2 == 0)
    {
        y = modexp(A, B / 2, C);
        y = (y * y) % C;
    }
    else
    {
        y = A % C;
        y = (y * modexp(A, B - 1, C) % C) % C;
    }

    return (ll)((y + C) % C);
}
//Books
int main()
{
    ll n, k;
    cin >> n >> k;
    ll a[n];
    for (ll i = 0; i < n; i++)
        cin >> a[i];
    ll left = 0, right = 0, ans = LLONG_MIN, curr = 0;
    while (left <= right && right < n)
    {
        curr += a[right];
        if (curr > k)
        {
            while (curr > k)
            {
                curr -= a[left];
                left++;
            }
        }
        ans = max(ans, right - left + 1);
        right++;
    }
    cout << ans;
}