from bisect import bisect_right
N = int(input())
material = [1]
diff = 2
for i in range(10000):
    sub = material[-1] + diff
    if sub > 10**7:
        break
    material.append(sub)
    diff += 1

start = bisect_right(material, N) - 1
ans = 1e18
for i in range(start, -1, -1): # 使う硬貨の最大値は material[start]
    nokori = N
    cnt = 0
    for j in range(i, -1, -1):
        # 貪欲に使う
        sho, amari = divmod(nokori, material[j])
        cnt += sho
        nokori = amari
    if ans > cnt:
        ans = cnt
print(ans)