#949. 2-bonacci
The first 2 terms are 1, and each next term is the sum of the previous 2 terms. Find the n-th term.
### Input
One integer n (1 ≤ n ≤ 60).
### Output
A number.
Examples
Input
49
Output
7778742049
Input
13
Output
233
💡 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.