#include <bits/stdc++.h>

#define NMax 1000002
using namespace std;
ifstream f("zombie.in");
ofstream g("zombie.out");

int d,n,k,x,y,i,t,start,starti,D;
int a[NMax];

int main()
{
    f >> d >> n >> k;
    for(int i = 1; i <= n; ++i){
        f >> a[i];
    }
    for(int i = 1; i <= n;){
        start = i;
        D = 0;
        while(a[i] - a[start] < d && i <= n){
            ++D;
            ++i;
        }
        if(i - start > k){
            t += k;
        }else{
            t += (i - start);
        }
    }
    g << t << '\n';
    return 0;
}