#include <iostream>
#include<vector>
#include<cstring>
#include<math.h>
using namespace std;
#define int long long
const int mod = 1e9 + 7;
vector<int> a;
int n, l;
vector<vector<vector<int>>> dp;
int sol(int mask, int cl, int prv) {
if (cl > l) return 0;
if (mask == (pow(2, n) - 1)) return 1;
if (dp[cl][prv][mask] != -1) return dp[cl][prv][mask];
dp[cl][prv][mask] = 0;
for (int i = 0; i < n; ++i)
if (!(mask & (1 << i)))
dp[cl][prv][mask] = ((dp[cl][prv][mask] + sol(mask | (1 << i), cl + ((prv == n) ? 0 : abs(a[prv] - a[i])), i)) % mod);
return dp[cl][prv][mask];
}
int32_t main() {
cin >> n >> l;
dp.assign(l + 1, vector<vector<int>>(n + 1, vector<int>(pow(2, n), -1)));
a.resize(n);
for (auto& x : a) cin >> x;
cout << sol(0, 0, n);
}
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