#include <bits/stdc++.h>
using namespace std;

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

const int NMAX = 1e6, INF = 2e9;

int d, n, k;
int v[NMAX + 2];

int ans, first = 1;

int main()
{
    in >> d >> n >> k;
    for(int i = 1; i <= n; i++)
        in >> v[i];

    v[n + 1] = INF;
    for(int i = 1; i <= n + 1; i++)
        if(v[i] - v[first] >= d)
        {
            if(i - first < k)
                ans += i - first;
            else ans += k;

            first = i;
        }

    out << ans << '\n';
    return 0;
}