URI Online Judge | 2846

Fibonot

By Francisco Elio Parente Arcos Filho, UEA BR Brazil

Timelimit: 1

The Fibonacci sequence is one of the most famous sequences in the world. The Fibonacci terms are always equal to the sum of the two terms preceding them in the sequence and the first two terms are 1. That is:

1 , 1, 2, 3, 5, 8, 13, 21, 34 ...

However, we are not interested in finding the terms of the Fibonacci sequence, but the terms of the Fibonot sequence!

The Fibonot sequence is composed of numbers that do not belong to the Fibonacci sequence. More specifically, non-zero positive integers. In ascending order!

Here are the first terms of Fibonot:

4, 6, 7, 9, 10, 11, 12, 14, 15 ...

Your task is to find the K-th Fibonot number.

Input

The entry consists of a single integer K (1 ≤ K ≤ 105) specifying the index of the element of the desired Fibonot sequence.

Output

A single integer representing the K-th term of the Fibonot sequence.

Input Sample Output Sample

1

4

3

7

6

11