#include <fstream>

using namespace std;

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

const int nmax= 1000000;

int v[nmax+1];

int main(  ) {
    int d, n, k, sol= 0;
    fin>>d>>n>>k;
    for ( int i= 1; i<=n; ++i ) {
        fin>>v[i];
    }

    int p= 1;
    for ( int i= 2; i<=n; ++i ) {
        if ( v[i]-v[p]>=d ) {
            sol= sol+min(k, i-p);
            p= i;
        }
    }
    sol= sol+min(k, n-p+1);

    fout<<sol<<"\n";

    return 0;
}