alternant

Task

We say that a natural number is alternating if even digits alternate with odd digits. For example, the numbers $236, 6, 12345678$ are alternating.

Given a natural number $n$, verify whether it is alternating or not.

Input data

The program reads the number $n$ from the keyboard.

Output data

The program will print da (yes in Romanian) if $n$ is alternating or nu (no in Romanian) if it is not alternating.

Constraints and clarifications

• $0 \leq n \leq 10^{15}$;

Example 1

stdin

785

stdout

da