n = int(input())
import math
ans = 10 ** 20
for j in range(0,100):
    if j == 0:
        ans = min(ans, 1 + 0 + n - 1)
    elif j == 1:
        ans = min(ans, n + 1)
    else:
        i = math.floor(pow(n, 1/j))
        ans = min(ans, i + j + n - i ** j)

print(ans)