from collections import deque

n = int(input())

nums = [0]
cnt = 0
loop_num = 1
loop_flg = True
while loop_flg:
    for i in range(1, loop_num):
        nums.append(i)
        cnt += 1
        if cnt == n:
            loop_flg = False
            break
    loop_num += 1

steps = [None, 1]
for _ in range(2, n+1):
    steps.append(-1)

q = deque([])
start = 1
q.append(start)
while q:
    v = q.popleft()
    # print('num')
    # print(v)
    # print('step')
    # print(steps[v])
    if v == n:
        # print("goal")
        break
    num = nums[v]
    for next_v in [v + num, v - num]:
        if 1 <= next_v and next_v <= n:
            if steps[next_v] == -1:
                q.append(next_v)
                steps[next_v] = steps[v] + 1

print(steps[n])