#include <stdio.h>
#include <stdlib.h>

int v[1000000];

int main()
{
    FILE *fin, *fout;
    int d, n, k, i, ac, j;
    fin = fopen("zombie.in", "r");
    fscanf(fin, "%d%d%d", &d, &n, &k);
    for(i = 0; i < n; i++){
      fscanf(fin, "%d", &v[i]);
    }
    fclose(fin);

    ac = 0;
    i = k;
    while(i < n){

      if((v[i] - v[i - k]) <= d){
        ac += k;
        j = i - k;

        do{
          i++;
        }while((i < n) && ((v[i] - v[j]) <= d));

        i = i + k + 1;
      }else{
        ac++;
        i++;
      }

    }

    if((i - k) < n){
      ac = ac + n - (i - k);
    }

    fout = fopen("zombie.out", "w");
    fprintf(fout, "%d", ac);
    fclose(fout);
    return 0;
}