n = int(input())

result = []

temp = n
if n < 26:
    result = [n]
else:
    while temp // 26 != 0:
        result.append(temp % 26)
        temp //= 26

        result.append(temp - 1)
print(result)


result = reversed(result)
result = ''.join([chr(i + ord('A')) for i in result])

print(result)