/* -*- coding: utf-8 -*-
 *
 * 634.cc: No.634 硬貨の枚数1 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_M = 10000;

/* typedef */

typedef vector<int> vi;
typedef queue<int> qi;
typedef pair<int,int> pii;

/* global variables */

int as[MAX_M];

/* subroutines */

/* main */

int main() {
  int n;
  cin >> n;

  int m = 0, sum = 0;
  for (int i = 1; sum + i <= n; i++, m++) {
    sum += i;
    as[m] = sum;
    //printf("as[%d]=%d\n", m, sum);
  }

  int cnt = 0;
  for (int i = m - 1; i > 0; i--)
    if (n >= as[i]) n -= as[i], cnt++;
  cnt += n;
  printf("%d\n", cnt);
  return 0;
}