import java.io.FileNotFoundException;
import java.math.BigInteger;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws FileNotFoundException {
		long t = System.currentTimeMillis();
		new Main().run();
		System.err.println(System.currentTimeMillis() - t);
	}
	
	void run() {
		Scanner sc = new Scanner(System.in);
		long N=sc.nextLong();
		int ans=0;
		while(N>0) {
			long p=1;
			while((p+1)*(p+2)/2<=N)++p;
			N-=p*(p+1)/2;
			++ans;
		}
		System.out.println(ans);
	}

	static void tr(Object... objects) {
		System.out.println(Arrays.deepToString(objects));
	}

}