#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<utility>
#include<cassert>
#include<complex>
using namespace std;

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
const ll mod = 998244353;
const ll INF = mod * mod;
typedef pair<int, int>P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef pair<ll, ll> LP;
typedef vector<ll> vec;
typedef long double ld;
typedef pair<ld, ld> LDP;
const ld eps = 1e-6;
const ld pi = acos(-1.0);
typedef vector<vector<ll>> mat;
typedef vector<ll> vec;

ll dp[301][5];
void solve() {
	int n; cin >> n;
	ll y; cin >> y;
	ll s = 0;
	vector<ll> a(n);
	rep(i, n) {
		cin >> a[i]; s += a[i];
	}
	vector<ll> ra(n + 1);
	rep(i, n) {
		ra[i + 1] = ra[i] + a[i];
	}
	ll ans = 0;
	rep(i, n) {
		if (i == 0)continue;
		rep(j, n + 1)rep(k, 5)dp[j][k] = 0;
		dp[i][0] = 1;
		for (int j = i + 1; j <= n; j++) {
			for (int l = i; l < j; l++) {
				ll sum = ra[j] - ra[l];
				if (sum + y < s / 5)continue;
				for (int k = 1; k <= 4; k++) {
					dp[j][k] += dp[l][k - 1];
				}
			}
		}
		for (int j = i + 4; j <= n; j++) {
			ll sum = ra[i] + (s - ra[j]);
			if (sum + y < s / 5)continue;
			ans += dp[j][4];
			
		}
	}
	cout << ans << endl;
}

signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	//cout << fixed << setprecision(8);
	//init();
	solve();
	stop
		return 0;
}

