#include <fstream>
#include <iostream>

using namespace std;

int D, N, K;
int v[1000005];

int main () {
    ifstream fin ("zombie.in");
    fin >> D >> N >> K;
    fin >> v[0];
    int j = 0, S = 0;
    for (int i = 1; i < N; i++)
    {
        fin >> v[i];
        if (v[i] - v[j] >= D)
        {
            if (i - j >= K) S += K, j = i;
            else
            {
                while (v[i] - v[j] >= D)
                    S++, j++;
            }
        }
    }
    S += min (N - j, K);
    fin.close ();
    ofstream fout ("zombie.out");
    fout << S;
    fout.close ();
    return 0;
}