[BOJ 15222] nnnnn
View as PDFHsara and Simone like to communicate without anyone else knowing what they’re saying. This time, Simone invented a very sneaky cipher. When she wants to tell Hsara a non-negative number n, she performs the following encryption procedure.</p>
Let d(n) denote the decimal expansion of n. Consider the string x := d(n)n , i.e., the decimal expansion of n concatenated with itself n times. The encryption of n is then the length of x.
As an example, assume Simone wants to encrypt the number 10. Then
x = 10101010101010101010.
The length of x is then 20, which will be the encrypted value of x.
Hsara had no problem writing a decryption algorithm for this procedure. But can you?
입력 형식
The first and only line contains an integer L (0 ≤ L ≤ 10106</sup>), the encrypted value of some non-negative integer n.
출력 형식
Output a single line containing the integer n.
예제 입력
20
예제 출력
10
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