#include <fstream>

using namespace std;
ifstream f("zombie.in");
ofstream g("zombie.out");
int d,n,k,Min,nr,s=0,a;
int main()
{
    f>>d>>n>>k>>a;
    Min=a;
    nr=1;
    for(int i=2;i<=n;i++)
    {
        f>>a;
        if(a-Min+1>=d)
        {
            if(nr<=k)s+=nr;
            else s+=k;
            nr=1;
            Min=a;
        }
        else nr++;
    }
    if(nr<=k)s+=nr;
    else s+=k;
    g<<s;
    return 0;
}