ayoAuY - Online IDE & Debugging Tool

#include <bits/stdc++.h>

using namespace std;
#define ll long long
const int maxn = (int)1e6 + 1;
int n, k;
vector <int> a(maxn + 1);
int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

	cin >> n >> k;
	for (int i = 1; i <= n; i++)
	{
		cin >> a[i];
	}
	vector <ll> pref(n + 1, 0);
	for (int i = 1; i <= n; i++)
	{
		pref[i] = pref[i - 1] + (a[i] - k);
	}
	stack <ll> st;
	for (int i = 0; i <= n; i++)
	{
		if (st.empty() || pref[i] < pref[st.top()])
		{
			st.push(i);
		}
	}

	ll ans = 0;
	for (int i = n; i >= 0; i--)
	{
		while (!st.empty() && pref[i] >= pref[st.top()])
		{
			ans = max(ans, i - st.top());
			st.pop();
		}
	}
	cout << ans;
}