#480. When a power of 7 goes over N
You get N. Find the smallest p with 7ᵖ > N.
### Input
One integer N (1 ≤ N ≤ 10¹⁵).
### Output
p.
Examples
Input
8956
Output
5
Input
54893
Output
6
💡 You can solve it with Python, JavaScript or blocks. Read the input line by line with input(). Don't print a question (like input("Number: ")). Print exactly what the output asks for, nothing more.