<gh_stars>0
# Uses python3

import sys

def get_fibonacci_last_digit_naive(n):
    if n <= 1:
        return n
    previous = 0
    current  = 1
    for i in range(n - 1):
        previous, current = current, previous + current
    return current % 10

def get_fibonacci_last_digit(n):
    if n <= 1:
        return n
    previous = 0
    current  = 1
    for _ in range(n - 1):
        previous, current = (current % 10), ((previous + current) % 10)
    return current

if __name__ == '__main__':
    input = sys.stdin.readline()
    n = int(input)
    print(get_fibonacci_last_digit(n))

# Uses python3

import sys

def get_fibonacci_last_digit_naive(n):
    if n <= 1:
        return n
    previous = 0
    current  = 1
    for i in range(n - 1):
        previous, current = current, previous + current
    return current % 10

def get_fibonacci_last_digit(n):
    if n <= 1:
        return n
    previous = 0
    current  = 1
    for _ in range(n - 1):
        previous, current = (current % 10), ((previous + current) % 10)
    return current

if __name__ == '__main__':
    input = sys.stdin.readline()
    n = int(input)
    print(get_fibonacci_last_digit(n))
# Uses python3