#include <fstream>

using namespace std;

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

int D, N, K, sol;

int main()
{
    fin >> D >> N >> K;

    int x, startX, ct = 1;
    fin >> startX;

    for(int i = 2; i <= N; i++)
    {
        fin >> x;

        if(x - startX < D)
            ct++;
        else
        {
            if(ct > K)
                sol += K;
            else
                sol += ct;

            if(i < N)
            {
                i++;
                fin >> x;
                startX = x;
                ct++;
            }
            else
                ct = 0;
        }
    }

    if(ct > K)
        sol += K;
    else
        sol += ct;

    fout << sol;
    return 0;
}