#include <fstream>

using namespace std;

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

int main()
{
    int d, n, k, minn, r, s=0, a;
    cin >> d >> n >> k >> a;
    minn=a;
    r=1;
    for(int i=2; i<=n; i++)
    {
        cin >> a;
        if(a-minn+1>=d)
        {
            if(r<=k)
            {
                s+=r;
            }
            else
            {
                s+=k;
            }
            r=1;
            minn=a;
        }
        else r++;
    }
    if(r<=k)
    {
        s+=r;
    }
    else
    {
        s+=k;
    }
    cout << s;
    return 0;
}