P14683 [ICPC 2025 Yokohama R] Decompose and Concatenate

You are given an integer greater than or equal to 2. When this number is decomposed into the sum of two **positive integers**, a new integer number can be formed as the concatenation of the decimal representations of the two integers. Find the maximum possible number formed in this way. For example, 102 can be decomposed and concatenated as follows. $$ 1 + 101 \ \rightarrow \ 1101 $$ $$ 2 + 100 \ \rightarrow \ 2100 $$ $$ 3 + 99 \ \rightarrow \ 399 $$ $$ 4 + 98 \ \rightarrow \ 498 $$ $$ \vdots $$ $$ 101 + 1 \ \rightarrow \ 1011 $$ Among them, $92 + 10 \ \rightarrow \ 9210$ is the largest.

The input consists of a single test case in a single line. The line contains an integer between $2$ and $10^{17}$, inclusive, which is the integer to be decomposed and concatenated.

Output the maximum possible number in a line.