#include <bits/stdc++.h>
using namespace std;
 
#define int long long
 
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
 
    int n, k, x;
    cin >> n >> k >> x;
 
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++)
        cin >> a[i];
 
    sort(a.begin() + 1, a.end());
 
    // r[i]: vị trí xa nhất có thể chọn nếu bắt đầu từ i
    vector<int> r(n + 2);
    int j = 1;
    for (int i = 1; i <= n; i++) {
        while (j <= n && a[j] - a[i] <= x)
            j++;
        r[i] = j - 1;
    }
 
    // dp[j] = kết quả khi xét từ i+1
    // newdp[j] = kết quả khi xét từ i
    vector<int> dp(k + 1, 0), newdp(k + 1, 0);
 
    for (int i = n; i >= 1; i--) {
        for (int jteam = 0; jteam <= k; jteam++) {
            // Không chọn i
            newdp[jteam] = dp[jteam];
 
            // Chọn team bắt đầu tại i
            if (jteam > 0) {
                int len = r[i] - i + 1;
                newdp[jteam] = max(newdp[jteam],
                                   len + dp[jteam - 1]);
            }
        }
        dp = newdp;
    }
 
    cout << dp[k] << "\n";
}

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

NSAyIDUKMSAyIDE1IDE1IDE1Cg==

5 2 5
1 2 15 15 15