import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;


public class Main_yukicoder33 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int d = sc.nextInt();
        int t = sc.nextInt();
        int[] x = new int[n];
        Map<Integer, Set<Integer>> hm = new HashMap<>();
        for (int i = 0; i < n; i++) {
        	x[i] = sc.nextInt();
        	int mod = (x[i] % d + d) % d;

        	if (hm.containsKey(mod)) {
        		hm.get(mod).add(x[i]);
        	} else {
        		Set<Integer> tmp = new TreeSet<>();
        		tmp.add(x[i]);
        		hm.put(mod, tmp);
        	}
        }

        long ret = 0;
        for (Set<Integer> hs : hm.values()) {
        	long tmp = 0;
        	long prev = Long.MIN_VALUE;
        	for (int e : hs) {
        		long r = e + (long)d * t;
        		long l = e - (long)d * t;
        		if (l > prev) {
        			tmp++;
        		} else {
        			l = prev;
        		}

        		tmp += (r - l) / d;
        		prev = r;
        	}

        	ret += tmp;
        }

        System.out.println(ret);

        sc.close();
    }
}