n = int(input())
res = n
for i in range(1, 1000000):
    for j in range(0, 100):
        if i ** j > n:
            break
        print(i, j)
        res = min(res, i + j + n - i ** j)
k = int(n ** 0.5)
res = min(res, k + n - k**2 + 2)

print(res)