Problem C
Tölvunarfræðingar telja

Picture from publicdomainvectors.org

Computer scientists count a bit different from normal people. Most people start counting at $1$, then go to $2$, and after that $3$ follows and so forth. But the first number according to computer scientists is $0$. Therefore the second number is $1$ and the $1337$-th number is $1336$.

Input

Input consists of one line with one integer $n$.

Output

Output the $n$-th number, according to computer scientists.

Scoring

1

0

2

1

1337

1336