# include <fstream>
# include <algorithm>

# define dim 1000005

using namespace std;

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

int a[ dim ];
int n, d, k;
int sol;

void citire()
{
 int i;
 f >> d >> n >> k;
 for ( i = 1 ; i <= n ; i ++ )
	 f >> a[ i ];
}

void rezolva()
{
 int i = 1, nr = 0, ok = 0;

 while ( i <= n  )
 {
	 nr = i;
	 i ++;
	 while ( a[ i ] <= a[ nr ] + d - 1 && i <= n)
		 i ++;
	 
	 if ( i - nr >= k )
	 {
		 sol = sol + k;
	 }
	 else
	 {
		 sol = sol + ( i - nr );
	 }
	 
 }
 g << sol  << "\n";
}


int main()
{
 citire();
 rezolva();
 return 0;
}