12. Up and Down

I'm a slow walker, but I never walk backwards.

Task Description

Write a program to read a positive integer $n$, then print a sequence of $2n-1$ integers from 1 to $n$, and then from $n-1$ to 1.

Input Format

There are one line in the input. The first line has the integer $n$.

Output Format

There are $2n-1$ lines in the output, according to the description.

Sample Input

5

Sample Output

1
2
3
4
5
4
3
2
1

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