#include <fstream>
using namespace std;

ifstream in("zombie.in");
ofstream out("zombie.out");


int main()
{
    int pr,consum=0,i,d,k,c=0,x,n;
    in>>d>>n>>k>>pr;
    c=1;
    for(i=2;i<=n;i++)
    {
        in>>x;
        if(x-pr>d-1)
        {
           if(c>=k)
                consum+=k;
            else
                consum+=c;
            c=1;
            pr=x;
        }
        else
            c++;
    }
    if(c>=k)
        consum+=k;
    else
        consum+=c;
    out<<consum<<'\n';
    return 0;
}