060. Maximum Number
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Find the largest possible number that can be stored with N bits. Assume that the number is a signed integer value. Remember that the maximum value possible with a certain number of bits can be calculated with the formula $$$2^{N-1}-1$$$. When solving this problem, keep in mind that if the input is greater than 32, your programming language may not have large enough integers, so you will need to use larger variable types or arbitrary precision arithmetic. Arbitrary-precision arithmetic comes with most programming languages, for example the BigInteger class in Java.

Input

An Integer N ranging from 1 to 64.

Output

An Integer representing the largest possible number within the given bit size.

Example
Input
32
Output
2147483647
Note

Be careful of floating point precision errors, and be sure that your output does not print output by a power of ten, e.g. 9.77E13.