#P1143B. Nirvana

    ID: 4692 Type: RemoteJudge 1000ms 256MiB Tried: 0 Accepted: 0 Difficulty: (None) Uploaded By: Tags>brute forcemathnumber theory*1200

Nirvana

No submission language available for this problem.

Description

Kurt reaches nirvana when he finds the product of all the digits of some positive integer. Greater value of the product makes the nirvana deeper.

Help Kurt find the maximum possible product of digits among all integers from $1$ to $n$.

The only input line contains the integer $n$ ($1 \le n \le 2\cdot10^9$).

Print the maximum product of digits among all integers from $1$ to $n$.

Input

The only input line contains the integer $n$ ($1 \le n \le 2\cdot10^9$).

Output

Print the maximum product of digits among all integers from $1$ to $n$.

Samples

390
216
7
7
1000000000
387420489

Note

In the first example the maximum product is achieved for $389$ (the product of digits is $3\cdot8\cdot9=216$).

In the second example the maximum product is achieved for $7$ (the product of digits is $7$).

In the third example the maximum product is achieved for $999999999$ (the product of digits is $9^9=387420489$).