#include<bits/stdc++.h>
using namespace std;
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("avx2")

using ll = long long;
//using i128 = __int128_t;
#define endl "\n"
#define int long long
#define db cout << "db" << endl;
#define x first
#define y second
typedef pair<int, int> PII;
const int N = 5e5 + 10;
ll inf = 2e18;
void solve() {
    int n, k;
    cin >> n >> k;
    vector<int> a(n + 1);
    int ans = 0;
    for (int i = 1; i <= n; i++) {
    	cin >> a[i];
    }
    map<int, int> ma;
    for (int i = 1; i <= n; i++) {
    	vector<int> b = a;
    	for (int j = i; j <= n; j++) {
    		for (int x = i; x <= j; x++) {
    			a[x] += k;
    		} 
    		for (int x = 1; x <= n; x++) {
    			ans = max(ans, ++ma[a[x]]);
    		}
    		ma.clear();
    		a = b;
    	}
    	
    	
    }
    cout << ans << endl;
}
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    int q = 1;
    //cin >> q;
    while (q --) {
        solve();
    }
    return 0;
}