#include <iostream>
#include <algorithm>
using namespace std;

int main(){
	int n, c, k, ans = 0;
	cin >> n >> c >> k;
	int t[n];
	for(int i = 0; i < n; i++) cin >> t[i];
	sort(t, t + n);
	for(int i = 0; i < n;){
		int now = 1, j = i;
		while(j < n && t[j] <= t[i] + k && now <= c){
			now++;
			j++;
		}
		ans++;
		i = j;
	}
	cout << ans << endl;
}