[1699][DP]

n = int(input())

dp = [x for x in range(n+1)]

for i in range(1, n+1):
    for j in range(1, i):
        if j*j > i :
            break
        if dp[i] > dp[i-j*j] +1:
            dp[i] = dp[i-j*j] + 1
print(dp[n])