题目描述
You are given an integer N.
For two positive integers A and B, we will define F(A,B) as the larger of the following: the number of digits in the decimal notation of A, and the number of digits in the decimal notation of B.
For example, F(3,11) = 2 since 3 has one digit and 11 has two digits.
Find the minimum value of F(A,B) as (A,B) ranges over all pairs of positive integers such that $N = A \times B$.
Constraints
- $1 \leq N \leq 10^{10}$
- N is an integer.
Input
The input is given from Standard Input in the following format:
N
Output
Print the minimum value of F(A,B) as (A,B) ranges over all pairs of positive integers such that $N = A \times B$.
Examples
Input
10000
Output
3
Input
1000003
Output
7
Input
9876543210
Output
6
输入格式
见题面
输出格式
见题面
样例输入
1000003
样例输出
7