The Eternal Immortality

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Codeforces

Easy

Math

Number Theory

Bit Manipulation

The Eternal Immortality

Compute the last digit of the infinite product of consecutive integers ending at $n$ modulo 10.

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Problem Statement

For a positive integer $n$ , consider the product

P = n \cdot (n+1) \cdot (n+2) \cdots \infty

This product is clearly not finite, so the useful interpretation is the one used in programming contests: determine the last digit of the value obtained by multiplying all integers from 1 up to $n$ ? No — for this problem, the key observation is that the required answer depends only on $n \bmod 10$ .

Given an integer $n$ , output the last digit of the value associated with the problem's eternal multiplication process, which is equivalent to the last digit of the product pattern generated by $n$ . The result can be found by looking at the repeated behavior of powers of 2 under modulo 10.

Input Format

A single integer $n$ .

Output Format

Print one integer: the required last digit.

Constraints

$1 \le n$ .
The answer depends only on the least significant digit of $n$ .

Examples

Sample cases returned by the problem API.

Example 1

Input

Output

Explanation

For $n=1$ , the answer is $1$.

Example 2

Input

Output

Explanation

For $n=2$ , the answer is $2$.

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Example 3

Input

Output

Explanation

The pattern repeats every 4 for powers of 2 modulo 10, and the last digit here is 5.

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