#include <fstream>
using namespace std;

ifstream is("zombie.in");
ofstream os("zombie.out");


int main()
{

    int d, n, k;
    int x, y;
    int cost = 0; //chakra
    int cnt = 0;
    int nr = 0;
    is >> d >> n >> k;
    is >> x;
    nr = x + d; //nr de timp pana la vrajitor
    cnt = 1; //nr de zombie
    int i = 0;
    int cnt2 = 2;
    while(cnt2 <= n)
    {
        is >> i;
        if(i > nr)
        {
            if(cnt >= k)
            {
                cost += k;
                cnt = 0;
                nr = d + i;
            }
            else
            {
                cost += cnt;
                cnt = 0;
                nr = d + i;
            }
        }
        else
        if(i <= nr)
        {
            cnt++;
        }
        cnt2++;
    }
    if(cnt >= k)
    {
        cost += k;
    }
    else
    {
        cost += cnt;
    }
    os << cost;


    is.close();
    os.close();
    return 0;
}