def solve():
    N = int(input())

    c = [0] * 16
    for i in range(1, 16):
        c[i] = c[i - 1]
        if i % 3 == 0:
            c[i] += 2
        if i % 5 == 0:
            c[i] += 2

    ans = (N // 15) * c[15]
    ans += c[N % 15]
    print(ans)


if __name__ == '__main__':
    solve()