#include <bits/stdc++.h>
#define Dim 1000001
#define Max 1000000012
using namespace std;
ifstream f("zombie.in");
ofstream g("zombie.out");
long long D,N,K,T[Dim],start,busy,rez;


int main()
{
    f>>D>>N>>K;
    for(int i=1;i<=N;i++) f>>T[i];
    start=T[1]; busy=1;
    for(int i=2;i<=N;i++)
    {
        if(T[i]-start>D)
        {
            rez+=min(K,busy);
            busy=0;
            start=T[i];
        }
        busy++;
    }
    rez+=min(busy,K);
    g<<rez;
    return 0;
}