mod = 998244353


def main():
    import sys
    input = sys.stdin.readline

    A = [2, 2, -1, -1, 2, -1, -1]

    D = int(input())
    x = 0
    ans = 0
    for _ in range(100):
        for a in A:
            x += a
            ans += abs(a)
            if x == D:
                print(ans)
                exit()


if __name__ == '__main__':
    main()