#!/usr/bin/env python3

INPUT_WHEEL_TEETH = 40
OUTPUT_WHEEL_TEETH = 8

with open('input.txt') as file:
    content = file.read().strip()

rotation_output = int(content) * (INPUT_WHEEL_TEETH // OUTPUT_WHEEL_TEETH)

print(rotation_output.to_bytes((rotation_output.bit_length() + 7) // 8, 'big').decode())