Units Digit of a Power of Two

Given a non-negative integer $n$, compute the units digit (the last digit of the decimal representation) of $2^n$.

Write a program that

• reads a non-negative integer $n$ from standard input,
• computes the units digit of $2^n$ in its decimal representation,
• prints the result to standard output.

The first and only line of input contains one integer $n$ ($0 \le n \le 10^{40}$).

Print the units digit of the decimal representation of $2^n$ on the first and only line.