Forbidden Zero

You are writing the positive integers in increasing order, starting from 1. You have never learned the digit 0, so you skip every number that contains a 0 in any position. The first ten integers you write are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 11.

You have just written the integer $n$, which contains no digit 0. Find the next integer you will write.

The first line contains the integer $n$ ($1 \le n \le 999999$).

The integer $n$ contains no digit 0.

Print the next integer you will write on the first line.