#include<fstream>
#include <algorithm>
using namespace std;
 
int i, N, D, K;
int x, nr, P;
int ANS;
   
int main() {
    freopen("zombie.in","r",stdin);
    freopen("zombie.out","w",stdout);
    scanf("%i%i%i", &D, &N, &K);
    for(i = 1; i <= N; ++i) {
        scanf("%i", &x);
        if(nr) {
            if (P + D > x)
                ++nr;
            else {
                ANS += min(nr, K);
                P = x;
                nr = 1;
            }
        }
        else
            nr = 1,
            P = x;
    }
    if(nr)
        ANS += min(nr, K);
    printf("%i\n", ANS);
    return 0;
}