Score : 100 points
We have a cord whose length is a positive integer. We will perform the following condition until the length of the cord becomes at most 2:
Let f(N) be the maximum possible number of times to perform this operation, starting with a cord with the length N.
You are given a positive integer X. Find the maximum integer N such that f(N)=X.
The input is given from Standard Input in the following format:
X
Print the value of the maximum integer N such that f(N)=X.
2
14