//Vasilut
#include<fstream>
using namespace std;
ofstream out("zombie.out");

int main()
{
    ifstream in("zombie.in");
    int n,d,k,zombie,p,x,bst=0;
    in>>d>>n>>k;
    zombie=1;
    in>>p;
    for(size_t i=2;i<=n;i++)
    {
        in>>x;
        if(x-p<=d)
            ++zombie;
            else
            {
            p=x;
            if(k>zombie)
            bst+=min(k,zombie);
            }
    }
        bst+=min(k,zombie);
        out<<bst<<'\n';
    return 0;
}